THE HOTSPUR GLIDER - WorldRadioHistory.Com · 2019. 10. 23. · Noverrfber, 1942 NEWNES PRACTICAL MECHANICS 37 Modern Workshop PracticeE PULL S By F. JOHNSTONE TAYLOR 780 PAGES 542

THE HOTSPUR GLIDER

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Noverrfber, 1942 NEWNES PRACTICAL MECHANICS 37

E PULL S

Modern Workshop PracticeBy F. JOHNSTONE TAYLOR

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VOL. X. NOVEMBER, 1942 No. 110

FAIR COMMENT BY TI-IE EDITOR

Invention and Post-war StabilityWE want more aggressive methods in

our Economic Organisation, bothto maintain our export trade

during the war and to prepare for the suddenand drastic change which is inevitable on thedeclaration of peace, says Sir Arrol Moir.

This problem should be given full con-sideration in the administration of ourtrade both within the country and the Empireand through our export trade with foreigncountries. It is true we are at war, but welearnt our lesson through the slump afterthe last war, which was created by thestagnation and change of trade during the warperiod.

Stagnation showed itself in many branchesof our trades which prosper in peace timewhen the present war was under a year old,and it is, therefore, our national duty now,in spite of war pressure, to find new stimulusfor our export trade and to eliminate thegrowth of this stagnation by the introductionof new ideas into our national industry. Thiscould be greatly assisted by the encouragementof every source of inventive talent in allclasses of the community and placing it beforethe many manufacturers and producers ofall sizes throughout Great Britain through anunbiased body. The Institute of Patenteesexists for this purpose.

For Post-war TradeTHE production need not be put in hand

now, while the war lasts, but contracts canbe signed and arrangements made that canbe put into force as soon as peace is estab-lished, so that this country and the BritishEmpire can start the fight for post-war tradesupremacy with advantage and establishedinitiative. This has proved to be possible inAmerica by a public body known as the MellonInstitute, which, after development throughfinancial support since 1913, has carried outinvestigation work for the inventor and put,through practical experiment, over 400inventions right that started in commercewrong. They now work in a building largerthan Buckingham Palace.

Such an organisation could be establishedin this country without interfering withexisting associations and institutions, but whichwould prove to be an asset to them after itsinitial development, as well as to all types oftrades and professions. It could be formedfrom the older brains of the country who donot wish to take an active part in the conductof the war, but who, through their pastexperience,, would be eminently suitable forsuch an important part and would be pleasedto put their activities to the development of anorganisation, the benefit of which couldbe world wide when peace has been finallyestablished.

ExhibitionsITS members would consist of inventors

and commercial firms whom the institutecould bring together through correspondenceand exhibitions, established in various in-dustrial centres throughout the country,to the extent of about four per annum,giving each an exhibition once in three orfour years, thus creating a sense of com-petition for the inventor, which would givehim greater power of introduction into theworld of commerce than he possesses atpresent and would allow all classes of inventorsto be treated on the same footing.

Such exhibitions have already been heldduring the last twenty years, both in Londonand other industrial towns, and in spite ofthe poor standard of exhibit available, haveall proved a financial success and createdinterest. One held in Sheffield attracted anattendance of 30,000 in ten days and ran at aprofit of over £600.

It is true that over 90 per cent. of theideas submitted would not be worth develop-ment, but if one or two of the remainder areworth investigation, a new industry may bestarted or an old one revived that will provideemployment for several thousand in a fewyears' time and become an asset to the country,and to the world in general at a later date,thus making the remaining 90 odd per cent.worth investigating to the full.

It is only when the bulk of the world isplunged into war, such as now, and in 1914,that the true value of inventive talent isrealised to the full and demanded. Encourageit also in peace time as well as in *Jar forthe benefit of trade and national heirrh andcomfort.

Preparing for the last war the Germansknew the value and strength of inventivetalent, as was shown by the Key IndustriesExhibition held in Westminster afterwards.There were shown some of the essentialitems needed in war -time, such as magnetosfor aeroplanes and lorries, heat -resistingglass for miners' lamps, optical glass forranging instruments, tungsten steel powderfor armour plating, etc., which were sold at afalse value through secret government sub-sidy to the rest of Europe for years beforethe commencement of hostilities, so thatwhen the latter was launched, their opponentswould not be able to supply themselves withthe additional quantities suddenly broughtinto demand by the expansion of war equip-ment without initial experiment and designcarried out by the inventive brains of theircountrymen.

Once our inventors' talent was fullyunder way and encouraged and investigatedby the Special Inventions Branch of theMinistry of Munitions, the absolute necessi-

ties were produced on a more efficient standardthan the. German and have remained so since,as is shown already in this war

New IdeasIN addition to the provision of existing

needs, new ideas, such as the tank andStokes' trench mortar, were introduced intothe army equipment through the Ministry'sactivities, which proved themselves to be ofinvaluable use to our Army ; and it has beenalready shown in the new war that the tankhas been included in the main attack on theWestern Front to the extent of over L000 aside, with many more of various sizes anddesigns to take their place as hostilitiesproceed.

This war was started with the neccasarytalent attached to the various governnIntalproduction departments for our fightingservices, but greater assistance might beprovided and the necessary work expeditedif liaisoh was established between theseand the inventive brains throughout thecountry, guiding and encouraging the latteron what lines to produce designs and sugges-tions as well as investigating ideas submittedfor acceptance or refusal as at present. Everyidea need not be submitted in secret, andthose that must can be put forward by eachside in a special way to avoid disclosure.

When once started, it could establish anexperimental station for the investigationof new inventions and for the research workof inventors which would carry out workunder contract for individuals and firms,and when established commercially, woulddo certain experimental work free of charge,acting under discretion for members who hadlittle finance, but whose ideas showed chanceof success if further developed on the rightlines. It would also form a technical committeeto consider the commercial possibilities ofideas put forward, who would seek the assist-ance of our other institutions.

Economic StagesTHE whole scheme could be set up to de-

velop in economic stages, each stage prOvingitself before the next was undertaken. Thiswas the system adopted by the MellonInstitute, and similar lines could be set upin this country, the inventions exploitedunder an unbiased technical supervision,being mutually profitable both to the inventorand the institute. Thus the latter couldgain funds to extend itself on an economicbasis and become a national asset in theadvancement of trade, defence and otherdevelopments of national importance,thereby reducing unemployment by thecreation of new and the revival of oldindustries.


40 NEWNES PRACTICAL MECHANICS November, 1942.

Gliders as War WeaponsThe Function of the Glider, with Particular Reference

to the Hotspur

AT the time of writing no British glidersor glider troops have gone into action.When the new front is opened up it is

certain that glider troops will be used if thepotential value of rhe air as a transportmedium is not to be neglected.

Some time ago we asked ourselves theultimate value of the small-scale commandoraids. Later we asked why we should lockup in this country vast forces of bombersand fighters when it seemed that they would jbe of more value in the Middle East. Whenthe first " r,000 -plus " raids were carriedout an answer of a sort was provided. Butbombing without a deeper significance thanmere destruction means that the tacticalpossibilities of the bomber are not being fullyrealised.

If we regard the commando raids aspractice raids, and the " r,000 -plus " raidsas preliminary bombardment testing out theeffects of large mass raiding, then the so-called " second front" proposals take on anew aspect.

We can assess roughly the magnitude ofthe offensive.

In the pattern of large-scale attack, glidersmust be an important piece. The glider isthe lorry of the air. The glider can putdown in one spot fully equipped men, whohave been transported at altitude and speed.Released at heights of to,000 feet the glidercan travel 3o miles, and come into its objectivesilently and at hedge height. Once the glideris down a compact body of fighting men isassembled.

The glider, made for the most part of wood,is not easily destructible. It has no engine

A class of glider pilots with their

to be disabled, no bombs to be touched off,no fuel to be ignited. It can absorb anamount of fire without going out of control.Once released it must be detected by sight orradiolocation.

instructor.

A line up of Hotspur glidersand one in actual flight.

Below : Immediately on landingthe crew get in touch with head-

quarters by means of radio

Troop MovementsThe purpose of the glider is to move

troops quickly and efficiently to where theywill do the most damage. The glider is nota highly finished weapon : in all probabilityit will make but one operational journey.It can therefore be made cheaply, and ingreat numbers without detracting from itsvalue.

The glider can be put down in a smallspace. Once down its use is over,' and onlyif there are ample men to spare would it beprofitable to recover used gliders duringoperational service.

Tug -machines and gliders need fighterescort when used on active service. Thebomber -tug -machine when towing cannot beso manceuvrable-any evasive action it mighttake makes the glider pilot's job difficult.But it is possible for tug -machine and gliderto dive without harm. It must be remem-bered always that the airborne troops mustfeel like fighting when they get down, and.violent banks and dives are not helpful inensuring this.

The speed of the tug -machine is onlyreduce -1 slightly by the addition of the glider.It has licen estimated that the Junkers Ju 52.



A glider in mid-air, being towed by the tractor aircraft.

towing a ro,000 lb. glider, has -its speedreduced by about 15 miles an hour. It hasalso, been estimated that towing a 7,000 lb.glider with a wing loading of to lb./sq. ft.causes only Hi miles an hour reduction inthe speed of the tug -machine. And all theBritish gliders known at present have 'anundercarriage which may be dropped afterthe take -off. The dropping of the under-carriage-in no case of retractable type-decreases drag considerably. Also, wheelsrequire a flatter landing ground and the skidstops the glider in a shorter space when theundercarriage is not attached.

Paratroops are invaluable for small-scaleraids, but in a gigantic attack wave after waveof gliders are required. Glider for paratrooptransport, the glider will always carry themore men. The size of the glider is limitedonly by the power of the tug -machine. Itis said that the Germans employ tank -carryinggliders. The weight of an armoured fightingvehicle can be' compared with the weight of5o fully equipped men.

Methods of EmploymentLet us sketch briefly the manner in which

gliders could be employed in the event of anoverseas attack. We will assume that the" second front " is being opened up.

First, aircraft carrying paratroops go over.Under air escort invasion barges withcommando troops go forward. Lightbombers and naval guns screen their landing..The naval units retire to port under airescort to pick up more men. Standing by are

- supply ships carrying artillery and mechanisedvehicles.

As the landing positions are consolidated' gliders are brought into action. They are

put down in a broad line forward of thelanding parties, and up by the paratroops.

It is now that forces of bombers go out' and bomb targets forward of the glider

Landing Heavy WeaponsIn the opening up of an overseas front the

most crucial hours are those during the landingof the heavy weapons. Fighter support inlarge numbers is indispensable and vital. Atthe moment of landing no invasion is im-mediately mobile. Thus, as with the glidertroops, the landing parties must be in touchwith fighter stations. The men on the groundknow where they need air support most.They must be allowed to say so.

Troops are equipped to fight in twodimensions. The air adds a third dimension.Therefore, the best answer to the aeroplaneis the aeroplane. It will not do all the timefor fighters to be away bombing the enemysupply lines and enemy troops advancing.Troops are equipped to deal with troops.The fight between ground troops andaeroplanes is unequal. And there is never anypoint in fighting unequal battles, howeverheroic, if such battles are avoidable.

It would be possible by means of the gliderto put down fully -equipped, men whereverneeded. Once the landing of troops, heavyartillery, tanks, armoured cars, and ant' -tankunits behind them has keen accomplished,the first iob of the glider troops has bean

Showing how a glider can land in ,a restricted space.

troops. Under cover offighters, ships must landtheir supplies of fieldartillery and armouredvehicles. As soon as themechanised divisions arelanded they must. berushed up to assist theglider troops and para-troops.

The glider troops a n dthe paratroops are themobile force. Theirchief weapon is sudden-

ness in striking, They must be reinforcedby heavy artillery and mechanised unitswith all speed. Their sole job is to main-tain a broad fan forward of the landing area.

Troopships must reinforce the landingparty by night, and destroyer screens must beset out to guard those troopships.

Losses among glider troops will be heavy.Their job is to hold this forward line for asking as possible without mechanised support.They must have the power to direct thesubsequent landings of gliders, so thatglider troops will arrive where the need ismost urgent.

The front part of a Hot-spur glider. Note thethree footholds whi ch.help the pilots toenter the cockpit.



General arrangementdrawings of the Hot-

spur II.

effected. They should then be withdrawnand re-formed.

As the invasion army, now firmly estab-lished, advances, so the glider comeinto use again. They can be sent over beyondthe immediate enemy forces. They couldward off the first blows of the approachingenemy. For the capture of enemy aerodromesand airfields they would be ideal. Droppingsilently out of the clouds gliders can dive, and,building up speed to nearly 170 miles anhour, come in hedge -hopping.

Glider troops are mobile. They can deliverrapier -like thrusts. They can weaken attacks bytaking the first blows. They are compact anddangerous. They are the cutting edge of attack.

Here is something of the history of theseglider pilots :

Glider Pilot TrainingAll glider pilots are volunteers from the

Army. And glider pilots at present flyingcome froth nearly all the units in the Army.If the volunteer is accepted he is transferredfrom his unit to an airborne division. Hedoes a course at airborne division head-quarters on the theory of flight, and othersubjects that will be of use to him later. Heis then transferred to an elementary trainingschool where, in a course of some weeks, helearns to pilot a light aeroplane. Here he doesa few hours' night flying.

He then goes on to a glider training school.Here he is put on to a troop -carrying glider.He flies on tow, and learns to land and theright moment to cast off the tow rope. Thetroop -carrying glider he uses has ballastinstead of live load.

When he is sent to the glider operationaltraining unit he does a course, and here hecarries live load. At the glider trainingschool he carried a parachute, but at hisoperational training unit he does not. Lecturesare also continued meanwhile.

He is released at great heights, and has tofind his way back; he is released at lowheights, and must again find his way back ;

HOTSPUR 11

also, he does somenight flying, so that bythe time he rejoins theArmy he is a full yqualified glider pilot.It is then that he getshis wings.

Glider troops weara plum -coloured beret,a shoulder flash withthe word " Airborne,"and a plum and bluebadge showing Bellero-phon mounting t h ewinged horse Pegasus.Glider pilots wear thesame, and, in addition,they have their"wings." Duringtraining they weartheir khaki uniforms.Their instructors aredrawn from the RoyalAir Force. Glider

pilots leave for the Army usually with therank of either sergeant or corporal.

Glider TypesDuring June the present writer visited one

'of the glider training schools. Hotspur Itswere being used (the Hotspur I has roundedwing tips and a greater span than the

Hotspur II), and it wasreckoned that pupils didbetween 8 and tt tripsbefore they go solo.a The Hotspur II,which was designed byGeneral Aircraft, Ltd.,is a midwing troop -

carrying glider, of wood construction, plywoodcovered. Makers of the Hotspur differ-many are furniture makers. The only fabricused is on the control surfaces.

The instruments include turn and bankindicator, altimeter, compass, air speedindicator, and rise and fall indicator. Dimen-sions are : length, 39ft. VI in. ; span,45ft. tin.; height, 'oft. loin. An estimatedcost for the Hotspur II is £5,500.

The Hotspur has dual tandem control, andduring training sand bags are strapped tothe seats at the back as ballast.

There are three ways into the Hotspur.The first and second pilots can get in (bythree footholds in the fuselage) through thecockpit covering, which opens back like a lid.The third and fourth crew can get in througha door on the starboard side, opposite No. 4seat. And the other members of the crewhave a door on the port side. All the seatsare numbered,and men wouldbe allotted toa definite pos-ition. TheHotspur h a sthe yellow andblack stripeson its bellyand underside C

wits wings,

which denoteof

the trainer.If manilla is used for the tow rope, it is

21 in. ; if hemp, 2 in. is used. Theropes are used for some 30 launches, andthen a new one is spliced on. A cablemaintenance gang checks the ropes afterevery launch. To lessen wear, the rope hasattached to it, at the glider end, a smalldrogue.

When the glider casts off the tug -machine the tug comes down fairlylow over the landing field and releasesthe rope. The end which the tug drops

falls to the ground first and the drogue keepsthe rope from buckling and crinkling as itgoes down. The drogue also guards againstwhipping before the rope is dropped.

During training not more than one glideris towed at a time. The idea that you canhave a . whole string of gliders, one tiedbehind the other, doesn't work out in practice.A lot of complications set in, and a " wave "makes life in the last one next to impossible.

Towing SpeedsThe maximum towing speed for the Hot-

spur is about, 16o miles an hour. Landingspeed is somewhere in the region of 8o milesan hour. At the. training school visited,Hawker Hectors were being used as tug -machines. They are very good for the job.

The best position taught at this school forthe glider when on tow is above the tug's slip-stream-other schools favour below the slip-stream. Close formation flying is not easy,either on tow or off tow, but it can be done.

An army marches on its stomach. It nowflies on it. In other words, the well -feelingof the airborne troops is essential. The firstthing that is required is that there shall beair, the second that there shall be light.Head cold, feet warm, is the ideal as far asventilation is concerned.

It is a fact that the morale of the soldieris not high after a lOng flight in a glider, whichhas little light and poor ventilation. Thismust be remedied. Glider troops mustalight with the .srge to do battle. If theyspend most of their time being sick theycannot be expected to feel like giving battle.It is essential that alterations which giveplenty of light and air in a glider should bemade.

To return for a moment to the tactical useof gliders, we can see that there is a very vitaluse for them in the broad strategy of invasion.Used in vast quantities, they would prove adeadly and fast -striking weapon.

There is great scope for the developmentof the glider. The first, and most obviousway, is in size. The German DFS 230AIis a to -seat troop -carrying glider with awing span of 69ft. I tin., and a length of37ft. Empty, it weighs 1,70o lb., loaded4,500 lb. It has an armament of one machine-gun. This is a small transport glider, whichwas first used over Crete.

The Gotha Go 242, illustrated On next page,carries 23 men, including two pilots. It istowed by the Junkers Ju 52, and has beenused in Libya. Armament is four machine-guns. The undercarriage is jettisonable.The nacelle is hinged at the rear to facilitateloading.

HOTSPUR I

A plan view of the Hot-spur I. A noticeable exter-nal difference between thistype and Hotspur II is inthe wings. In the lattertype the wing tips are

squared up.


November, 1942The DFS 230 At is classed as small, the

Gotha Go 242 as medium. What thecapacity of the large troop -carrying gliders iscan only be guessed, but already reports havecome through which state that the Germanshave gliders capable of transporting too men.

Mobility DevelopmentsApart from sheer size, there is room for

development in the mobility of the glider.Experiments have been carried out in theUnited States whereby the glider, once landedand its load taken off, is picked up by a tug -machine which remains in the air. At themoment it is not generally assumed to bepractical for gliders, once down, to be re-trieved and used again within a short spaceof time. If the American experiments provesufficiently successful to be put into operationaluse it means that the number of gliders neededis lessened. It also means, and more im-portant, that the tug -machine can circle untilthe glider is emptied of its troops and thencome down low and pick up the glider which,except, of course, for the glider pilot, isempty. Thus the tug -machine serves auseful purpose on the return trip.

The United States Airborne Command,which is under the direction of ColonelWilliam C. Lee (he commanded the Pro-visional Parachute Group before), has, as itsprogramme, the formation of regiments

" If at First .

A LITTLE episode . . . it might be called" devotion to duty " : in the R.A.F.

squadron records it is entered without com-ment. Yet everybody, from the squadron

NEWNES PRACTICAL MECHANICS

of parachute units and alsoairborne infantry units. And gliderunits, drawn from the Air Forces,are to be attached to the Commandfor training troops in glider trans-port. The scheme appears, there-fore, to be much the same asour own.

We learn that glider production is beingpushed ahead in Germany, in America, andin Britain. The thriller headline, " Invasionby Air ! " we used to see on our pennydreadfuls is no longerschoolboyish fa n t a sy.Speed is the essential.Gliders confer speed onany airborne army. ThereWill come the time whensuch an army will go intoaction.-[By the courtesyof the Editor of " Aero-nautics."]

43

52..6"

General arrangement drawings of the GothaGo 242. This German glider has a capacity for23 fully equipped troops.The glider empty weighs

2,3001b. and loaded8,5oolb. The central

nacelle is 37ft. long.

Aero Notes

commander downwards, knows what itrepresented. An aircraft, having just taken offfrom a Coastal Command aerodrome, caughtfire in one engine. It was heavy with bombs,fuel and ammunition.

The pilot-a 2t -year -old flight lieutenant-headed for the sea. There he got rid of hisembarrassing load of bombs, and landed again

without mishap. It was an inky dark night andthe landing was in itself something of a feat.Though the fire was now extinguished theaircraft was unserviceable. But the pilot andthe crew had a job to do. If they had receiveda shaking they did not show it. They clam-

bered into the stand-byaircraft and took offagain, all well withinthe hour from theirfirst attempt.

(Above). Briefing thecrews of bombers before

taking part in a raid.

(Right). The sting inthe tail of a Wellington

bomber.

790

GOTHA 242

Lancaster and Lightning ShockFLYING through an electric storm over

the North Sea, a Lancaster bomber wassuddenly wrapped in a flash of blue lightand tossed out of control. All four enginescut out, and the bomber nose-dived for6,000ft. at more than 400 miles an hour.The captain tugged at the control columnand his second pilot tugged too.

The gunnerthen struggled out of his turret,and climbed up to the cockpit, where he workedthe wheel controlling the elevator trimmingtabs. Between them the three men broughtthe Lancaster out of its dive when it wasonly about 400ft. above the water. Theengines started again, and the crew finishedtheir journey home.



Electric Fire-arms

THE very effective light machine-gun-model M 26 of the Brno Zbrojovka-called the Bren gun in the British

Army, possesses a theoretical rate of fire of600 per minute. This amounts to an ammuni-tion consumption of two and a half times ofits own weight for this short period.

This rate of firing is multiplied in specialmodels, used in aerial defence and aerialattack, by the method of coupling the barrels.For this purpose, an extremely high rate offire is necessary in a comparatively shortperiod. This problem has been solved bysimply coupling together the machine-gunbarrels and their loading mechanism. Bycoupling of five barrels, theoretically and fora short time-for a few important seconds-also actually, a rate of fire of five times 600,that is, 3,000 shots per minute are possible.

But in spite of all these decisive construc-tive improvements, the primitive fundamentalprinciple has remained unaltered-the utilisa-tion of the explosive power of the charge.Not only is this explosive power used to hurlaway the projectiles, it must also operate thewhole complicated loading process. Recoilloaders, in which the recoil of the cartridgeis used to operate the loading mechanism, arejust as primitive as the gas -engine loaders, inwhich the gas, generated in the barrel, passesinto a cylinder and actuates the breechmechanism.

We can best compare this process with onewe are well acquainted with in our every-day life. When we use a typewriter, thefingers must not only release the type bars,they must also simultaneously perform theprocess of writing by exerting the muscle

The Possibilities of the Electrically Operated CentrifugalGun and the Solenoid Howitzer

By K. DOBERER

power of the fingers. In the modernhigh-speed typewriters, however, these.two processes are detached from eachother. The releasing, the- command,is carried out by a light pressure of the

fingers. The loadingprocess and the actualwriting process from oneletter to the next areperformed by an electro-motor.

In the same way, ofcourse, a separation ofthe loading processfrom the actual firingprocess can be under-taken in the machine-

gun. Machine-guns in fixedpositions o nconcrete fortifi-cations enableus to fix thecables for elec-tro-motorswhich then gives

Our artist's impression of a centri-fugal gun, driven in this instance byan internal-combustion engine, capableof projecting bullets at an exceptionally

high rate per minute.

us the opportunity to use the electro-loadersystem NT/here the charge only performs theactual forcible firing process. All loadingmovements are carried out by the electro-motor. The result is a much smootherfunctioning of the whole loading process,and possibilities for new constructional workare created which may lead up to a con-siderable increase in the rate of fire. Decisiveimprovements of this description may beattained especially for multiple machine-guns to ward off enemy air attacks on placesof strategical importance and on ships ; onplaces, therefore, in which the supply ofammunition is safeguarded at the same time.

In how far electro fire -arms will also beemployed in the trenches, and in positionwarfare, only depends upon one question-in how far the big problem is solved of thesteady supply of current for an army by theuse of steel -plated cables or by employingwireless transmission of power.

Long-range Centrifugal GunA German patent describes a control con-

trivance of the loading mechanism for thesteel projectiles of mechanical sling weapons,fitted with a centrifugal rotor, specially de-signed for use in fighter airplanes.

A few years ago it was reported thata Japanese had also constructed a machine-gun,driven by an internal combustion engine, andworked by means of a revolving disc, possess-ing an aperture on its face, which fires no lessthan 9,900 shots per minute. The Americanswere also said to be carrying out similarexperiments, and to have made an inventionof the same nature as the Japanese gun with

which they even can fire 33,000 shots perminute. These bullet-slingers, says the re-port, must certainly not be over -estimated,as they are no match for the customary modernfire -arms as far as the hitting power and theaccuracy of aim are concerned. Nevertheless,it is interesting that efforts are being made touse our modern machines also as the motiveforce for weapons.

Of course, we must not take the wholereport as fact, but it gives us- an indicationabout certain experiments going on in severalcountries. There is a hint in the report onthe part which our modern machines willplay in the development of the new weapon.But the most modern of our machines, theelectro-motor as motive power for the cen-trifugal machine-gun is not even mentioned.And it is just the electro-motor, as we shallsee later on, which offers the best possibilitiesfor the increase of the so much distrustedaccuracy of aim. The actual result of this seriesof reports is, however, that public opinion, ona certain scale, has become acquainted withthe " Death Centrifuge "-it has now beenprojected out of the hazy distance of Utopia

into the sphere of reality.Utopia already had seized

upon this weapon a few yearsago. In the year 1932, a novelby Ilja Ehrenburg, the Russianwriter, " Trust for the Destruc-tion of Europe," was published.In this book a bombardmentby 28 electric centrifugal guns-the system was named " Cen-trifuge Divoire Excelsior "-is described. These bullet-slingers were, so the novelgoes, constructed by a French

engineer in the year 1928, and consisted oftwo large steel discs, running at a speedof 2,000 revolutions per minute.

Let us briefly allude to the fact that thisidea, which has now become reality, is notthe only possibility of discarding the powder -recoil weapons. The air -gun was alreadymentioned in the cited report. To -day it isgenerally only used as a sporting gun. Butmany efforts have been made to make thistype of weapon a requisite of war. TheMilitary Historical Collection in Prague, forinstance, possesses a repeating air -gun,constructed by Girardoni somewhere aboutthe year 1770. The gun was 12 -chambered.The necessary compressed air was pumpedinto a reservoir in the gun stock with a handpump. The first of the 12 shots carried as faras zoo paces, whilst the last ones had practicallyexpended their force when they left thebarrel. By the use of motor -driven com-presses a far more rapid series of shots orlarger bores in connection with a considerablyincreased range would be attained. Owing tothe noiselessness of its operation, the employ-ment of this principle for hand grenadesSeems to be quite feasible. But this gun, andalso all the patented gas -guns with theirexcellent electrical ignition, will alwaysremain insufficient where projectiles are tohave a certain piercing power when theyreach their mark. Contrary to the air- andgas -propelled fire -arms, the centrifugal gunpossesses this property, as it is based on thetheoretically unlimited power of centrifugalforce. After a certain probationary period itwill certainly be able to compete with ourpowder -recoil weapons in the most instances.



The Rotating BulletLet us consider the terrific speed with which

every ounce of steel on the periphery of thelarge wheels of modern turbines revolves. Iffrom one of the turbines of a giant liner aparticle of steel was hurled away it would travelat a speed of 300 yds. per second. It wouldpenetrate a human body like a bullet, as thevelocity of a bullet fired from an ordinaryrevolver, when it leaves the muzzle, reaches aspeed of 280 yds. per second. Only theprojectiles from modem army pistols with aninitial muzzle velocity of 35o yds. persecond would overtake the particle of steelhurled off by the turbine. Using nickel steelblades for the turbine we can, however, go upto peripheral speeds of 400 metres per second.It is therefore possible to construct acentrifugal machine able to hurl steel particlesfrom its outer rim at speeds much higher thanthe initial velocity of projectiles from armypistols.

In the United States of America separatorswith duralumin rotors were built for scientificresearch with which peripheral speeds of725 yds. per second were registered. `Thephysicists Beans and Weed, of VirginiaUniversity, succeeded in reaching 500,000revolutions per minute with their supercentrifuge, which, however, has a correspond-ingly smaller' diameter of the rotor disc.During experiments which Professor Beanswas carrying out, a rotor of 3iin. diameterburst whilst doing 132,000 revolutions perminute. This works out a " muzzle velocity "of 65o yds. per second for the outer partson breaking away.

It may be assumed that, if suitable newlight metal alloys are used, peripheral speeds-and these, and not the number of revolu-tions are the chief thing-of about i,000 yds.per second could be secured without strainingthe material to the breaking point.

The achievement of serviceable peripheralspeeds, which here means firing velocity, can,

therefore, hardly be doubtful for thu centri-fugal machine-gun.

Compared with the old types of fire -aimsthe centrifugal machine-gun will be greatlysuperior in its rate of fire. The first centrifugalmachine-gun, constructed in the year 1918by the American, W. Lombard, in Boston,theoretically fired no less than 33,000 shots inone single minute. This large number ofshots was a logical result of the construction ofthe Death Centrifuge. Thirty-three thousandshots per minute means that 55o projectilesare hurled out every second. Five hundredand fifty is-at the same time-the number ofrevolutions of the two flat steel discs runningtogether closely. After every revolution thesediscs throw, from a slit in the rim, a steelbullet out of the discharge aperture. Thenumber of revolutions is necessary, if, with adisc diameter of min., an initial velocity ofnearly 800 yds. per second is to be achievedby the bullets. This initial velocity, which isincreased by the radial action of the centrifugalpower, imparts more energy to the round steelbullets of the centrifugal machine-gun, althoughthey only possess one -quarter of the weight ofthe heavy lead -filled pistol bullets. The steelbullets in the Death Centrifuge roll in a steadystream into the machine through the axis.Then they are carried to the rim, moving upto top speed, by a fluted spiral curve-thefluting being stronger and stronger towardsthe outside. By this system it is possible to

Is this the howitzer ofthe future ? Animpression ofan electricsolenoidgun

Huge projectiles,perfectly stream-lined, are hurledthrough space bymeans of power-ful electro-mag-

netie fields.

increase the speed of the bullet from noughtup to 800 yds. per second in a comparativelyshort period.

The Water -hose MethodIn keeping with the uncommon character

of the recoilless shot, it must be assumedthat the accuracy of aim of the DeathCentrifuge within a certain range can beincreased without any difficulty compared,with the result's obtainable with powderrecoil weapons, so that the very contrary ofsuperficial predictions comes to pass. It isnot an actual disadvantage of the centrifugalweapons that it is not possible to simplytake direct aim over the straight barrel ofthe gun with them. By an anticipated methodof calculation, the aiming contrivance andthe distance adjusting apparatus are socoupled that if they are properly regulated,there is the same guarantee for the exactitudeof aim of the projectiles as with the powderrecoil weapon. It will then be a matter ofindifference to the marksman which curveshis bullets may take before they hit theirmark.

As the actual power of every weapon isdependent upon the proper limitation of itsuse, it stands to reason that this principlealso applies to the centrifugal machine-gun.It is a typical hand-to-hand fighting weaponlike the tommy gun. Its confines lay in theimpossibility to increase the initial velocityover a certain point, owing to the limitedqualities of the materials used for its con-struction, which even the most up-to-datealloy combinations cannot overcome. Afurther limit is given in the aerodynamicallydisadvantageous form of the bullet comparedwith the long stream -lined projectile usedin modern fire -arms. The steel bullet fromthe centrifugal gun is not an armour piercer,although it is asserted that during rests anarmour plate, fin., was penetrated by a shotfired at a distance of fifty paces from a

- centrifugal gun.The proper utilisation of an ultra quick -

firing gun can be demonstrated by the water -hose method introduced during the Englisharmy manoeuvres. During machine-gunoperations so many tracer bullets wereinterposed in the ordinary ammunition ofthe belts that there was a line of fire from themouth of the gun to the target of thesesheaves of bullets. Similar to the functioningof a fire hose, the gunner no longer adjustshis aim by means of the sight, but simplyby the line of light. By employing thismethod, hits were scored in the shortesttime, even against such difficult targets aslow flying battle 'planes. The ultra -high rateof fire of the centrifugal machine-gun is anindication for its use in a similar manner.

But even for this purpose, the rate of fireused by the first mentioned inventor is toohigh. Even if one takes into considerationthat copper and lead are not required for thistype of gun, the consumption of steel by arate of fire of 33,000 shots per minute is toohigh. In Japanese tests the rate of fire hasbeen reduced to 9,000 shots per minute.

To attain this number of shots, the numberof revolutions of the rotating disc was reducedto 150 per second. Of course, the diameterof the disc had to be accordingly enlarged,so as to ensure the necessary bullet velocityof 800 yds. per second.

A smaller number of shots is possible, itafter every shot the next bullet enters thefeed only after several revolutions of thewhirling discs have taken place. To enablethis, an electro-magnet, coupled with therotor between the bullet magazine and thefiring groove, ist provided ;according to aGerman patent) which releases the steelbullets in a certain rhythm. This rhythmcan, of course, be made variable, so thatdifferent rates of fire result. similar to theEnglish Lewis machine-gun.


46 NEWNES PRACTICAL MECHANICS Nlovem.:.s.er, 1942The Solenoid Howitzer

A steel shell, thrust by the force of hugemagnet fields, through a barrel -long systemof rings of solenoid coils, and leaving thenthe mouth of the solenoid howitzer --noise-lessly, but with incredible speed-that is thescientifically ideal application of the electro-gun. Although in all big guns the aimingcontrivances are already electrically operatedand even the initiative to the propelling force,the char ge explosion, is given by electricity,this primeval force of nature so far was onlya servant of the great force of the explosivewhich ultimately flung the projectile, weighingmany tons, out of the barrel with a rumblingdetonation.

Now the same work is to be, performed bya series of enormous electro-magnets, out ofwhich American engineers have constructedthe barrel of an amazing howitzer. One afteranother, each of the series of strong coils pullthe heavy steel shell up to the centre of itsring. At the same moment, however, thecircuit is broken, and only the long row of thecoil rings higher up in the barrel attract theshell. This makes it impossible for the ringsalready passed to develop counter forces, andthe shell is drawn through the barrel at aspeed increasing from coil to coil.

It --may be added that this method maysupply the propelling power for several othertypes of war machines. We may mention thetorpedo release and the throwing of mines..These ballistical contrivances may offer betteropportunities at once and then prove usefulfor the further development of the idea rightup to the ideal solenoid howitzer. Thedominant advantages of this new method tothrow projectiles are quite obvious. Insteadof a heavy gun, weighing hundreds of tons,a steel -ribbed construction suffices, perhapsonly weighing the tenth part of the weight ofa " Dicke Berta." The cost per shot of about£200 can be reduced considerably if,instead of an explosive charge of many hundredkilograms, the high -tension from the electro-power station is able to supply the energydirect. Deformations of the ordinary gunbarrel, making it unserviceable after a smallnumber of shots, are impossible with thesolenoid howitzer, as the projectile is forcedto keep exactly to the centre line of thebarrel by the magnetic field and, therefore,does not even touch the walls of the barrel.There will be an economisation of metal, asthe copper driving bands, which must producethe- spinning of the projectile, are, with theelectric gun, superfluous-and copper is animportant metal in war -time. The rotationof the projectile on its own axis during flight,so necessary for stability and always a sourceof the greatest difficulties with heavy guns,can be achieved by magneto -electric effectswith the solenoid gun. Sound, smoke andflash of discharge-a constant worry tomilitary experts-are entirely done away within the electro-gun. Even the slight reportof a pneumatic shot, the shot by air pressurewhen the compressed air is released, does notobtain with the solenoid gun. Whilst theshot is being fired, the air can have free accessto the steel frame behind the projectile, orit can even be pressed in at the moment offiring to avoid drag-the resistance of air.Projectiles for the solenoid gun do not, ofcourse, possess the imperfect aerodynamicform still necessary for those of the powdergun, with its flat base, exposed to air reaction,which tends to reduce the motion. They areconstructed in streamline contour in perfectaccordance with aerodynamical principles andtaper to a point at the tail. Consequently, thedecrease in velocity is much smaller and tocover the same trajectory they can start witha lower initial velocity.

Should we have any doubt about gainingthe initial velocity of- the powder recoil guns-the 210 millimetre (8.26in.) long-distdnceguns, firing into Paris during the Great War

from a distance of 13o kilometres, possessedan initial velocity of 1,600 metres per second-we must remember that the normal velocityat which electricity responds is 300,000kilometres per second. During a lectureNicola Tesla once stressed this point, referringto the incredibly short time which suffices tobuild up big forces in electro-technics. Teslasaid

" Such results are easily achieved, as thecondenser can discharge the accumulatedenergy in an inconceivably short time.Nothing known in physics can equal thisproperty.

" As far as its effect is concerned, apowerful explosive like dynamite can bestbe compared with a- charged condenser.But even the tremendous explosive powersof dynamite cannot be compared with thoseof a discharge or an explosion of a con-denser. The pressure produced by thedetonation of chemical compounds can bedetermined by dozens of tons per squareinch, whilst a condenser discharge willamount to thousands of tons per squareinch. If one could produce a chemicalpreparation able to explode with the samevelocity as a condenser charge, one ounceof it would be enough to put the mostpowerful battleship out of action."Thus the possibilities existing in the exploita-

tion of electric percussive forces- were clearlystated. Therefore the problem is reducedto the question of the mastery of such forces.Many large laboratories devote their work tothe study of finding a solution.

A Shot Out of the EarthTo reduce the budget expenses connected

with such special investigations as much aspossible, other possibilities for the applicationof the driving power of the solenoid coils arebeing searched for and technically perfectedin various laboratories.

As we have already pointed out, the decisivedifference between the driving power of thesolenoid coils and that of gaseous substancesis that the former do not exert any pressure onthe walls of the tubes, so that, in the workproceeding in Moscow, the brass tubes, whichotherwise would have been necessary, can besubstituted by simple papier mache tubes.

The small steel projectiles, containing the

goofs about to be transported, are hurledforward through _the electro-magnetic fieldsof the solenoid coils placed along the papiermache tubes. In view of this properlyfunctioning plant, we can understand howthe solenoid howitzers, with their big, closelypacked magnet coils, will convert mightycurrent impulses into extreme acceleratingpower. A standard work on ballistics, editedby a number of leading artillery experts andpublished in 1939, gives the following dataabout an electro-magnetic gun :Length of the tube .. 27.5 metresCalibre of the projectiles 47.5 centimetresWeight of the projectiles 3,000 kilogramsInitial velocity of the pro-

jectiles r,000 metres persecond

In addition, unbelievable figures relating tothe rate of fire are given.

In Russia, designs for a gun of this kindhave been made by Professor A. A. Koroljkoff,who demonstrates that such guns can be oper-ated both by direct current as well as byalternating current. Of course, it is notpossible simply to connect up such guns withthe next point-the heavier ones require quitea fair -size power station for themselves.

In his design for a gun of this type, Pro-fessor Koroljkoff bases his caIculat'on onenergies available from a power stationwhich has a capacity of roo,000 kilo-watts. His gun is only to fire projectiles witha calibre of six inches, weighing approxi-mately 4o kilograms, but these projectiles areto leave the tube with an initial velocity of90o yds. per second and with a rate of fire ofzoo shells per minute.

These figures are, it is true, theoretical, butthere is no doubt that such guns are alreadyunder construction.

Objections raised by experts, that thebarrels of the solenoid guns have to be toolong to _be practical, are unfounded. Thetubes of the electro-magnetic quick -firinghowitzers can be run into the ground in pits,and the range can partly be regulated by thestrength of the current. Guns of this kindcan be excellently employed for the purpose ofdirecting the most rapid and continuous fireon certain predetermined objectives, or pointswhich the enemy has to pass under all circum-stances.

Modern porn poloanti-aircraft guns on board a destroyer.



Aircraft Detectors

oystal Microphone

SINCE the outbreak of war many devicesfor the locatipn of aircraft in flighthave been studied and developed. One

electro-acoustic method, which has beenproduced in commercial form in this countryby Benjamin Electric, Ltd., comprises anaccurate metal parabolic reflector, with adiameter of 3ft., mounted on a massive turn-table which is placed on the roof of a building.The turntable enables the complete reflectorto be turned through 36o degrees, while an-other control permits the angle of elevation tobe adjusted to any degree. Located precisely atthe focal point of the parabolic reflector is amicrophone (piezo crystal or a special dynamictype) and surrounding the outer periphery ofthe reflector is an acoustic tube adjusted inlength so that it acts as a Helmholtz resonator.This resonator not only increases the soundmagnification but it also markedly reduces

.m.+90v

+135 v.

/5v PSv

Fig. 2.-The amplifier circuit. Values of the various components arc : Ri, R2, R4, R7, Rio,ioo,000 ohms ; R3, R6, R9, 300,000 ohms ; RS, RI t, R13, 500,000 ohms ; R12, 3,000ohms ; R5, 500,00o ohms ; all resistances rated at o.5 watt. Cs .00025 : C4, C6, C8.

o mfd. ; and C3, 8 mfd. electrolytic

1

Fig. t.-The aircraftdetector in position

for operation.

wind noises and pick-up due to mechanicalvibration.Signal Output

The signal outputfrom the microphoneis fed into a high -gainamplifier incorporat-ing a special filternetwork, so that itacts as an acousticband-pass filter. Bymeans of a selectorcontrol , differentbands of audio -fre-quencies can beaccepted and a 11other signals attenu-ated. The outputfrom the amplifier

is applied to a pair ofheadphones and/or to the" Y " plates of a cathode-ray tube. In operation,by rotating the reflectorunit, which resembles asearchlight in appear-ance, in the direction ofthe aircraft a low audio -frequency signal will beheard in the headphones,and as the reflector isadjusted carefully theintensity of the sound willincrease or decrease, de-pendent on the directionof flight.

Crystal MicrophoneEmploying the same

C6

C7

Rock' WoolPlug

Aeroplane "Spotting" by Electro-acousticalMethods

By D. W. ALDOUS, M.Inst.E.

method, but in a less elaborate form,the Department of Physics at RensselaerPolytechnic Institute, Troy, New York,has developed an aircraft detector foruse by observers in the smaller towns andvillages in rural areas of the U.S.A. outsidethe audible range of air-raid sirens installedin the bigger towns, and themselves lackingadequate warning of the approach of enemyaircraft.

This detector consists of a crystal micro-phone, with a large loudspeaker horn acting asa sound collector, plus a battery -operatedamplifier feeding earphones. The micro-phone mounting is shown in Fig. 3, and itshould be noted that the function of the loud-speaker horn, admittedly not designed for thepresent purpose, is to act as a sound collectorand is not intended to resonate at any par-ticular frequency.

Throat of Horn

11111

11111j11111111110111111111111 1 111111111

inCra

I

V41,

Air -tightSeal

Rigid Metal Shield

Fig.

Output

Celt

Pl2

3.-The crystal microphone

Amplifier CircuitThe amplifier circuit is shown in Fig. 2, and

any high impedance L.F. amplifier valves aresuggested as being suitable for VI, V2, V,3with a low impedance output valve for V4.One feature of it is deserving of special men-tion. The keynote of the complete detector issimplicity combined with cheapness, and inattaining this end a novel form of outputcircuit, which dispenses with the conven-tional choke or transformer, is used. Theoutput is taken, via a o.t mfd. .condenser,from the cathode (filament) circuit of valveV4. Although a low impedance output valveis recommended, its anode resistance isspecified as 3,000 ohms, and so when usedwith a pair of high -resistance earphones, say2,000 ohms, an optimum circuit of averagevalue is obtained. Also, even if R shouldfail a tolerable performance could still beeffected by the earphones resistance alone.The possibility of shock to the operator fromthe H.T. supply, in the event of failure of theoutput condenser C8, is removed owing to thevalve action in not passing reverse current.

Cost of EquipmentThe equipment seen in Fig. t is said to

cost the equivalent of £m, and its range ofsensitivity is sufficient to give the " spotter "enough time to prepare for recognition.

ShieldedMicrophoneCable

AstaucMicrophoneCartridge

\1

---,RubberMountingRing

mounting.



A Beaufort torpedo -bomber. These machines are now operating against enemy ships in the Mediterranean.

The World of AviationThe Whirlwind Germany's New Bomber : The Typhoon A Backyard 'Plane :

All -metal Amphibian 'Plane New Russian 'Planes : Jet-propelled 'Planes

The WhirlwindAN announcement stated that the Whirl-

wind, one of our newest fighters, hasrecently been in action. It is a single -seattwin-engined 'plane, powered by two Rolls-Royce Peregrine engines, each of 35o h.p.Its armament consists of four zomm. cannon,and the Whirlwind has a speed of nearly400 m.p.h. The range of the tighter is fairlyextensive. The Whirlwind was taken off thesecret list last March.

Germany's New BomberTHE Heinkel 177, Germany's new bomber,

is an unusual aircraft with a maximumrange of over 7,000 miles, with a 15 per cent.overload, and carrying i,000lb. It has fourMercedes-Benz engines, each of 1,460 h.p.,but appears to have only two, for each pairis built into one nacelle, and geared to drivea single propeller. With a wing span ofro3ft. and a length of 67ft., this giant -of theair, strange as it may seem, is fitted for dive-bombing, having dive brakes beneath eachwing. When loaded for a maximum rangeflight, the Heinkel 177 can carry finder half aton of bombs, but for what the Nazis callnormal range, between 2,0oo and 3,000 miles,its load is about that of our Lancaster. Ithas a top speed of just over 300 m.p.h., acruising speed of t8o'm.p.h. and a ceiling of25,cooft. The machine is well armed, havingamong other armament features a gun turretunderneath the fuselage both fore and aft ofthe wings. It has a crew of seven. So far,the Heinkel 177 has not carried out anyoperational flights.

The TyphoonQ SINCE the Typhoon came into existence,

as far back as February, 1940, it has beentest -flown by Flight-Lieuts. P. W. S. Bulmanand Lucas, until to -day it is turned out as thefastest interceptor fighter in the R.A.F. Itis similar in appearance to the Hurricane, butthere the similarity ends. The Typhoon ismuch faster (its speed is said to be well over4.0o m.p.h.), and it climbs with amazingspeed. Two men, Sydney Camm, who designedthe machine, and Frank Halford, designer ofthe engine, are responsible for the Typhoon.Naturally the specification of this fighter is a

close secret, but it can be said that the enginedevelops 2,400 h.p. and its short length addsconsiderably to the manoeuvrability of theTyphoon and may account for the statementthat it can stand on its tail and still go onclimbing. It is a fitting reply to the Focke-Wulf 190.

A Backyard 'PlaneAN American aircraft firm have during

the past year been carrying out experi-ments with a 'plane which can be flown withabsolute safety from suburban gardens. Itcan be built for as little as Lisa. During teststhe machine has shown its ability to rise anddescend vertically regardless of wind or calm.It has hovered motionless above the groundwhile men on the ground have changed oneof its tyres, and hovered a few inches abovethe head of a man on the ground for half anhour. The machine can fly backward,forward and sideways. An amphibian modeltaxies forward, sideways or backward, againstany current of wind, and turns round andround on the same spot. It will land on seaor grass without any adjustment. Themachine has a top speed of about 90 m.p.h.and is said to be practically fool -proof. Itcan be mass-produced.

New Aircraft Engine PlantsANEW aircraft engine plant, so huge that

it will house its own indoor road,highways and villages, is being rushed tocompletion by a large aeroplane company inAmerica. The Chrysler Corporation is alsobuilding a huge plant at Detroit, where airengines of tremendous power will be built.

500 Flying ShipsHOWARD R. HUGHES and Henry J.

Kaiser, the civil engineer who revolu-tionised American shipbuilding, are joiningforces to build a. fleet of Soo huge cargoflying -boats to carry war supplies to thefront. The 'planes will be designed by Mr.Hughes and made by Mr. Kaiser. Mr.Kaiser's idea to build J these huge machineswas based on the 7o -ton Mars carrier aero-plane built by the Glenn L. Martin Company.

The Mars can carry 150 troops with fullequipment.

New U.S. Fighter" A NEW American fighter which is in the

400 m.p.h. class will be delivered onall fronts," said Major -Gen. Brett, commanderof the United Nations air forces in the South-west Pacific, in Philadelphia recently. " Itflies fastest above 25,0ooft., weighs 5,000lb.more than the ordinary fighter, and possessesfire-power equivalent to a five -ton lorrysmashing into a stone wall at 6o m.p.h."

All -metal Amphibian 'PlaneAN amphibian machine which has been

giving a good account of itself recentlyis the Grumman " Goose," an all -metal'plane which heavily armed for both offen-sive and defensive work. Powered by two450 h.p. engines, the " Goose " has a maxi-mum speed of zot m.p.h., a ceiling of 22,00oft.,and carries a oral, of three or four. Arma-ment features include a fixed machine-gun inthe nose and a free one at the back. Bombscan be carried under each wing.

The Japanese Zero FighterWE have heard quite a lot about the Zero

fighter which the Japanese are using inthe Far East, and although the American andBritish fighters are superior in both speed andarmament, the Zero fighter cannot be dis-missed lightly as a second-rate machine.Early models had only two machine-gunssynchronised to fire through the propeller,but the aeroplane was so light and compactlybuilt that it had amazing manoeuvrability.If an opponent got on its tail the Zero wouldgo into an amazingly steep climb and thenflop over backwards on top of its pursuer.This sensational loop was niade in about3ooft. Most other fighters would needi,000ft. to do the same thing.

It is now rumoured that the Zero fighterhas now been equipped _with special robot -pilot devices. If in a dog-fight the Japanesepilot finds himself at a disadvantage, hemerely hands over to the robot pilot, whichthen hurls the aeroplane around in the skyin a manner with which no human can cope.



Britain's finest. bomber-the Lancaster-in flight.

New Russian MachinesWE hear that Russia is developing several

types of heavily armoured high-speedfighters, but she is very secretive about theircapabilities.

The Focke-Wulf 190IT is now learned that Kurt Tank, the

designer of Germany's No. I fighter,the Focke-Wulf 19o, has succeeded in con-centrating the major weight, engine, tanksand pilot tightly around the centre of gravityso that the machine has exceptional manoeu-vrability. It will also be able to be fitted witha more powerful engine when one becomesavailable.

Jet-propelled 'PlanesITALY are still experimenting with their

jet-prdpelled planes, but what resultshave been achieved in this field are not yetknown. A descriptive article on this type ofaeroplane appeared in a recent issue ofPRACTICAL MECHANICS. Instead of an air -screw, air is sucked through the nose, ex-panded by heat, and shot out of a narrow holein the tail in such a way as to provide a power-ful forward thrust for the aeroplane.

Giant AircraftTN reply to a further question in the House" of Commons recently about cargo -carrying aircraft, the Minister of AircraftProduction, Colonel Llewellin, stated thatorders had been placed in this country and asuitable production programme arranged.The Minister added that, with the assistancewe hoped to get from the United States, asubstantial number of these aircraft should beavailable.

Picking Up GlidersRECOVERY of a glider once it has reached

its objective and discharged its load hasbeen an hitherto unsolved problem in militaryaviation. The U.S. Army Air Force areexperimenting with what may be the answer.As will be seen from the illustration on thispage, the gadget consists of two poles fromwhich is suspended a rope which runs alongthe ground to the glider. The towing 'planedrags a hook over the rope in a low swoop,and the glider is hooked just like a mailbag. The glider then becomes airborneonce more, as shown in the illustration.

The Spitfire VTHE Spitfire V , which has recently been

taking part in a number of fighter sweepsacross the Channel is now fitted with animproved engine, and is armed with twocannon and four machine guns. As an. all-round 'plane it compares favourably with theHurricane, being swift, high -flying, easy tomanoeuvre in the sky and deadly in fire-power.

Target -towing AircraftANEW aircraft, the Miles Martinet 1, built

by Phillips and Powis Aircraft, Ltd.,has been introduced into the R.A.F. for towingtargets for firing practice. It is a two -seat,low -wing monoplane of wooden construction,

and is powered by a Mercury XX or MercuryXXX air-cooled radial engine. Transmittingand receiving radio units are fitted. Provisionis made for fitting desert equipment. It ispossible to tow either sleeve or flag -typetargets.

Seagull Scout 'PlanesCURTISS WRIGHT'S versatile Seagull

scout 'planes are now serving with theU.S. Fleet. A two -seat monoplane for land -based or catapult operation, the Seagull'slong cruising range and its ability to carrylight bombs make it a menace to submarines.

The Carter TrainerBY an ingenious device known as the

Carter trainer, the A.T.C. lads ofWood Green, London, get useful practice indummy bombing. It was built by the boysunder the supervision of their commander,and all the instruments work as accurately asthose of a real 'plane.

The MustangMUCH has been said about the Mustang,

the American one -seat single-enginedfighter. It is an all -metal monoplane of thelow wing cantilever type. It is not unlike theGerman Me. 109E in appearance with itssquare -cut wing -tips. This is due to thestraight lines of the Mustang's wings, tail-planes, and rudder, but it lacks the ratherungainly body lines of the German machine.The Mustang is powered by a liquid -cooledAllison 1,15o h.p. engine, and has a wingspan of 37ft. Sin. and is 31ft. 3in. long.

Lockheed and ThunderboltMR. EDWARD RICHENBACKER,

American flying expert, has 'told Armyradio technicians that the two Americanfighter 'planes, the twin-engined Lockheedand the Thunderbolt, have both provedsuperior " in actual tests " to the Focke-Wulf19o. The Lockheed, he says, climbs as highas a Spitfire, and flies faster, and the Thunder-bolt will go higher.

Method of picking up gliders after they have discharged their load. (See paragraph:on this page.)



Odd Jobs

Fig. 2.-Mixing the coal dust and cementIN order to economise to the utmost in the

use of coal, it is necessary to burn up allthe coal dust. A good method of doing

this without causing a lot of smoke is to formthe coal dust into briquettes ; these can beburned in the same manner as ordinary coalblocks, which are obtainable ready-made.

The dust for making the briquettes shouldonly contain fine particles of coal, and piecesof appreciable size must. be burned in theordinary way. The reason for this is that thefine dust binds more uniformly.

One of the simplest bindingagents for holding the dusttogether in the form of briquetteis Portland cement, a sevenpound bag of which will besufficient for making severaldozen briquettes.

Fig. 3.-Tamping downthe coal dust and cementmixture in the moulding box.

First of all a simple moulding box willbe required, and this can be made with piecesof wood lin. thick, to the dimensions given inFig. 1. Nail the parts together as shown, sothat spaces between the partitions measureroughly 6in. by 3in. by ain.

Next, an old bowl or similar receptacle,of fairly large size, will be required, in whichto mix the coal dust and cement, in the pro-portion of 16 parts of coal dust to r part ofcement ; add water, a little at a time, andmix the ingredients well, until a stiff,mortar -like consistency is obtained. A handytool for the mixing process is a small gardentrowel, as shown in Fig. 2.

When the mixture is ready place themoulding box on a flat board, fill -the spaceswith the mixture and tamp it down with athick square piece of wood, as indicated inFig. 3. After the blocks have been formedthey can be pressed out from the mouldingbox and put on one side to dry for about24 hours before being used. Although thebriquettes will not burn exactly like solidcoal, when put on a hot fire they will burnaway slowly, thus saving coal.

in House and Garden

in an oil

12"

bowl.

8.-Making Briquettes : A Cinder Sifter

Using Fire -bricks

Clay as a BindingAgentInstead of using

cement, ordinarygarden clay can beused as a bindingagent. The clay shouldbe moistened till itforms a thick pastymass, the coal dustbeing added andmixed thoroughly withthe clay, and then formthe mixture into balls,

V

Fig. 1. -A simplemoulding box for

making briquettes.

by hand, or press themixture into woodenmoulds to form bri-quettes, as previouslydescribed. Smallflower pots can also beused for moulds. Afterbeing formed thebriquettes should beplaced on a shelf in adry shed to dry andharden before beingplaced on a fire.

The Paper BagMethod

Another simplemethod of utilisingcoal dust is to sprinkleit with waterthoroughly to dampenit, and then place it intosmall bags roughlymade of 'pieces ofsoiled thick brownpaper. If brown paper

94,

By

1/

"HANDYMAN"

is not available, any old piece of newspaperwill answer the purpose. Use two or threethicknesses of paper for each, bag, and packthe dampened coal dust in as tightly aspossible, without bursting the bag. Tiethe bags round with a piece of wire intwo or three directions and they are thenready for use. If the bags are placed oneat a time on an open fire, the contents willburn away slowly like an ordinary coal block.

A Cinder SifterAn old method of economising in the use of

coal is to burn the cinders over again. This;however, usually proves tobe rather a dusty job, butwith the easily made sifterillustrated herewith,cinders can be collectedwithout any mess or dustflying about. The sifterconsists of an outer con-tainer, in the top part ofwhich is a sieve, coveredby a loosely fitting lid.

Two handles a r e alsoprovided.

The container can bemade from wood, to the dimensions givenin Fig. 4. Cut away part of the bottom edgesof the ends to form feet, as indicated, andfix the parts together with r in. French nails.Two fillets, cut from r lin. by yin. batten, arescrewed to the inside of the container 4in.from the top edge to form supports for thesieve. A piece of yin. plywood cut to thesize required and screwed in place forms thebottom of the container.

The sides of the sieve can be cut from kin.wood, the parts being either screwed or nailedtogether. Cut a piece of sin. -mesh wire

9"

Fig. 4.-The sieve and casingthe cinder sifter.


November, 1942

Fig. 5.-Method of fixing wire nettingbottom of the sieve tray.

netting to correspond with the overall dimen-sions of the sieve frame and fix it in placewith a few wire staples. Clamp down theedges of the wire netting with strips ofwooden lath nailed in place, as shown inFig. 5. Small pieces of wood can be screwedto the ends of the sieve tray, on the inside, toform finger grips to facilitate the removal ofthe sieve (Fig. 4).

A shallow, loose -fitting lid with sides about

to the

NEWNES PRACTICAL MECHANICS 51-

2in. deep can be made with in. plywood, or to lie warmed, a simple improvised heaterpieces of packing -case wood, The lid covers can be made with two garden flower pots and athe container while the sifting is being doneand prevents the spreading of dust. To holdthe sifter firmly whilst shaking to and fro, eithera metal or wooden handle can be screwedto each end of the sifter, as shown in Fig. 6.

Using Fire BricksConsiderable economy can

the use of coal or coke bythe use of firebricks,especially in open grates.These bricks are obtain-able in various shapesand sizes, and the bestmethod is to place one,specially shaped for thepurpose, at the back ofthe grate, or one on eachside. By this means upto .50 per cent. of thetotal grate space can betaken up by firebrickswhich become red hotand give off a consider-able amount of heat,after the fire has beenalight for some time.

An Improvised HeaterIn cases where a small

room or shed ha

he effected

tallow nightlight. Select the clean pots,one 6in. diameter, and the other about Sin.Place the larger pot where it is required tostand, put in the lighted nightlight, and thenplace the other pot (inverted) so that it restsin the top part of the larger pot. After anhour or two, a -pleasant warmth will be

in noticeable.

Tank Pro ress

Thsee columns of " Churchill" heavy infantrytanks lined up prior to taking part in exercises.

" Churchill TanksSINCE the Dieppe raid, in which some of

the " Churchill " tanks taking partwere unfortunately left in the enemy's hands,some interesting illustrations and particularsof these formidable machines have beenreleased.

There are several types of this machine,but the principal difference is in the armamentcarried. The latest type, the " Sprintern,"has a 6 -pounder gun mounted in the turret,and also a coaxial machine gun which istrained with the 6 -pounder, but can be firedindependently. Some of the tanks are fittedwith a 2 -in. gun in the turret, and a 3 -in.howitzer below it. All the types havesimilar tank bodies, and nine carrying wheels,or "bogies,".on each side. The engines,transmission gear, and tracks are aLso commonto all types: The turrets and tank bodies aremade of specially hardened armour plating.

The "bogie"wheels are carriedon short radiusarms, providedwith helicalcompres s i onsprings. At therear, on the side ofthe tank shown inthe right-hand illus-tration, is seen theair intake louvresfor cooling theradiators, which arejust behind it. Atthe extreme rear isan auxiliary petroltank which can bejettisoned. w hen

Fig. 6.-The complete sifter.Neat in appearance and very

effective in use.

necessary, from inside the tank. The" Churchill " has a surprising speed, buton account of its heavy armour andformidable fire power it can also be usedas a pill -box.

Welded ConstructionConsiderable progress has been made in

the United States in fabricating tanks by arcwelding. Two problems in connection withthis process, that of welding armour plate,and the provision of welding shops withequipment for permitting large tank sub -.assemblies to be rotated into different posi-tions -for flat welding the joints, have beensuccessfully overcome. Two types of thesewelded tanks are now in service, the " M3"and the " M4,- and both have a heavy arma-ment.

One of the new "Churchill" tanks travelling at speed on manteuvres, somen, ere inthis country.



MASTERS OF MECHANICSNo. 79.-The Rev. William Lee, and His Invention of the Stocking Frame

IT is a rather curious fact that mechanisedknitting, despite its greater complexity,was first attempted at least a century

and a half before mechanised weaving.Knitting, of course, differs from weaving inthat it consists of the art of entwining a singlethread in such a manner as to produce afabric, whereas weaving comprises the com-bining of two or more threads for the pro-duction of cloth or textile fabric.

Weaving is older in history than knitting,but in chronological sequence knitting comesfirst, for, seemingly, inventors tried to devisea machine which would knit automaticallybefore they brought into being the nowadayscommonplace loom of weaving machine.

There is a good deal of mystery, to saynothing of romance, surrounding the firstcrude attempts to devise a knitting machine.It is recorded that the art of knitting stockingsarose in Scotland at about the beginningof the sixteenth century, whence thetechnique passed to France, in which countrya considerable industry was founded upon it.

As the sixteenth century progressed thepractice of knitting became more and morewidespread and popular. Knitwear stockingswere worn both by royalty and the noblesand by the poorest of people. Stocking -knitting became as important an industry ashand -loom weaving.

First Mechanical KnitterThe creation of the first mechanical knitter

towards the end of the sixteenth century is ofmuch interest in view of the fact that apart,of course, from the inventionof the spinningwheel and the early weaving loom, both ofwhich devices are older than recorded history,it comprises the first of the long and highlyingenious series of inventions which, in theeighteenth and nineteenth centuries, so greatlyrevolutionised the textile industries.

Precise details concerning the constructionand mechanism of the first mechanical knitter,or " stocking frame," as it was called, havenot survived the passage of time. There is,as we have previously mentioned, an atmo-sphere of mystery about the entire circum-stances of this pioneering and immenselynoteworthy invention.

It is tolerably certain, however, that themechanical knitting frame, the first of thetextile inventions, was the outcome of experi-ments made by one William Lee, a clergyman,who was, for a time, curate of Calverton, thena village about five miles distant from Not-tingham. Lee, although supposed to havebeen born at Calverton, was, so far as canbe ascertained, actually a native of Wood -borough, another Nottinghamshire village.The date of his birth is unknown, norare we aware of any of the circumstancesof his early career apart from the facts that hebecame an Arts graduate of St. John's College,Cambridge, and that he ultimately tookHoly. Orders.

Lee must have been a fairly young manwhen he first devised his stocking framein or about the year 1589. Shakespeare wasliving at that time, and Queen Elizabethwas on the throne of England. British trade wasincreasing throughout the world, making ourcountry rich and prosperous. Yet, strangely,the invention of the stocking frame broughtto William Lee no lasting pecuniary rewardsor fame. On the contrary, it enshrouded him

in miseries and vexations and, in the end,it led him to a condition of almost abjectpoverty.

Pioneer inventorThe Rev. William Lee, one of Britain's

first if not the pioneer mechanical inventor,was an inventor who failed. Perhaps hismechanised stocking frame may not have been

The first means of supplying power for textilemills in Englandthe water -wheel.

a very efficient one, for we have few detailsof it. Rather, however, Lee was an inventorwho was before his time, for all forms ofmechanisth in the days of Elizabeth and,indeed, for long after the close of her reign,

The. first mecktnised silk mill

were regarded with ineradicable prejudiceand suspicion. Steam power, of course, hadnot yet come. Any crude mechanisms, there-fore, which happened_ to be built up by aningenious craftsman or inventor had still tobe powered by hand or, at the most, by meansof mechanical energy derived from a water-wheel or similar device.

There are several stories relating to theRey. William Lee and his invention of thestocking frame. The most reliable one has itthat Lee was expelled from CambridgeUniversity for marrying contrary to thestatutes of his College. His wife, the storyruns, was compelled to practise stockingknitting in order to contribute to the slenderfamily funds, and it was in consequence ofwitnessing her continually active fingers thatLee conceived the idea of his stocking frame,thereby lightening his wife's burden in thisrespect.

Whatever truth there may be in this story,it is evident that William Lee actually didinvent some kind of a mechanical knittingmachine, probably a hand -turned multi -needle affair, which he set up and operatedsuccessfully for a time in Nottinghamshire.

But Lee was a man of ambition. He wantedmore than merely local renown for hisstocking. frame. He took the device toLondon with him, set it up in his apartmentsin Bunhill Fields, on the outskirts of thatcity, and eventually prevailed upon no less apersonage than the Queen herself to do himthe honour of witnessing -the performance ofhis invention.

Queen Elizabeth Refuses PatentThere is a tradition that Queen Elizabeth

was accompanied by Lord Hunsdon whenshe visited Lee. The stocking frame, toLee's delight, worked perfectly and evenamazed the Queen. Whereupon my LordHunsdon urged the monarch to favour thestruggling clergyman by granting him apatent for his remarkable invention, Towhich appeal the Queen is reported to havemade the following reply :

JUIEMIIITTEBT,

11)1111117111111jUr"

11-1,(1111.1111

in England. Situated at Derby, on the River Derwent.


November, 1942 NEWNES PRACTICAL MECEIANICS 53

A modern automatic loom for cloth weaving. The outcome oftwo centuries of evolutionary effort in the textile industry.

My lord, I have too much love for mypoor people, who obtain their bread by theemployment of knitting, to give my assent tothe forwarding of an invention that will tendto their ruin by depriving them of employ-ment, and thus make them beggars. HadMr. Lee made a machine that would havemade sills stating, I should, I think, havebeen somewhat justified in granting him apatent for that monopoly, which would haveaffected only a small number of my subjects,but to enjoy the exclusive privilege of makingstocking for the whole of my subjects is tooimportant to grant to any individual."

Lee Settles in LondonIf the English Queen really did make this

pronouncement to Lee she failed to discouragethis inventor, for, obtaining ample encourage-ment from Lord Hunsdon, who in con-sideration of a share in the proceeds of theexpected future patent, advanced sufficientfunds for carrying on further inventive work.Lee at once settled down in London, not onlyto improve his original stocking frame (whichwould only knit coarse hose), but also. tocontrive a machine having 'twice the numberof needles which would knit stockings in silk

"In these activities Lee seems to have hadthe assistance of Sir William Carey, son ofLord Hunsdon, who was actually boundas apprentice to Lee.

Little or nothing came of Lee's effortr, inconjunction with Sir William Carey, but, ata subsequent date, Lee, in association withhis brother, James, contrived, after manylong and tedious trials, to build up an arrange-ment of needles soldered into brass combswhereby plain silk stocking could be producedfrom what was then termed " twenty gaugesilk " thread.

Hosiery IndustryDuring this period, Lee had endeavoured

to keep a small hosiery industry running inNottinghamshire. He also erected nearly adozen of his new " silk frames " in Londonin anticipation of Queen Elizabeth's finallygranting him the much -desired patent for hisinvention.

In all these activities, Lee had workedprincipally with a small staff composed ofhis own relatives together with a few trustedapprentices.

In 1596, Lee had erected his ninth frame "in London and was hopeful of obtainingQueen Elizabeth's coveted patent protectionfor his invention. Unfortunately, at- this;uncture Lord Hunsdon, who was virtually a

partner in the enter-prise, died. To makematters worse,Hunadon's son, SirWilliam Carey, Leesapprentice, also diedat about the sametime.

Queen Elizabeth,then at the zenith ofher dictatorial power,refused to encourageLee any further with

"his inventions. Shedeclined to grant himany patent for eithera woollen or a silk -knitting " frame."On all 'sides, theunfortunate clergy-man -inventor metnot only with dis-couragements, but,in addition, with, 'attimes, active hostility.Like many an in-ventor, he was

accused of taking -the bread.-our of the mouthsof the workers. His "frame " was, decriedby the many, although the few rook to con-structing copies of it for themselveS andso defrauding the inventor of the legitimateproceeds of his ingenuity.

Lee Leaves EnglandAt last, worn, weary and despairing of any

further encouragement, Lee deterMined toleave England: The news of his intentionreached the ears of the French Ambassadorin London. The ambassador showed himselfinterested in Lee's stocking frame. Heoffered the hospitality and good feeling of hiscountrymen to Lee and to his brother if theywould remove themselves, together with. aselected number of their workmen, to Francefor the purpose of erecting " frames '! andoperating the latter in that country, -

Lee gratefully received this offer. At oncehe made plans for the setting up of hismechanised industry in Rouen. But all sortsof vexatious delays and mishaps intervenedto prevent his prompt removal of men,machines and material to that noted city.Several -years, in fact, elapsed before Lee andhis brother had set up their " frames " in

Rouen And when eventually Lee announcedhis readiness to start off in Rouen with hismechanised knitting, the news of the tragicassassination of the French king, Henry IV,resounded throughout the whole of France:

Henry I V of France, through his ambassadorand other officials, had encouraged Lee in his -creative efforts. But with the untimely demiseof the king Lee seemed to have a presentimentthat all was lost for him.

At any rate, his former cheerfulness, forti-tude and determination in the face of activediscouragement. completely deserted him at -this stage. He fell into a condition of melon"-choly from which he never recovered.

His DeathIt is said that the Rev. William Lee died in

a garret in Paris in 161o, the year of theFrench king's assassination. Certain it is thatWilliam Lee was never heard of again, and,for this reason alone, the story of his death inParis is probably an accurate one.

After Lee's death, his brother, James Lee,together with the diminutive band of workerswho went over to France from England,decided to return to their native shores.Together, they endeavoured to operate the -stocking frame secretly in one or moreobscure Nottinghamshire villages. Had theybeen abfe to do so, the Lee " stockingframe " might never have been made public.

As matters were, however, a miller ofThoroton, in Nottinghamshire, managed toobtain the secret of the construction of Lee's" frame." This man, whose name was Aston,subsequently set up on his own account, and,seemingly, he was the only man who evermade anything out of the project. Aston mustundoubtedly have had innate mechanicalability, for he appears continually to haveimproved the stocking frame, and to have gonefar to found a stocking and knitwear industrywhich not only sufficed for our country's needsalone, but also for the beginnings of anexport trade to other nations.

In the 17th century English -made stockingsattained a degree of celebrity on the Continent.English knitted silk stockings were exportedto Italy in unusually large amounts.

Thus was created a prosperous Englishindustry by the invention of a singlemechanical principle.

A Lancashire .landscape which depicts an industrial vista. far removed from any of whichthe Rev. William Lee may have dreamed.



Aircra t Pneumatic EquipmentDetails of the System as Used on Military Aircraft

By T. E. G. BOWDEN, Grad.R.Ae.S., M.I.E.T. -

COMPRESSED air is used mainly tooperate the wheel brakes, but is alsoemployed in military aircraft to

operate the armament and in certain cases asan undercarriage emergency lowering system.Flaps and landing lamps are also sometimesoperated by means of compressed air. Theflying instruments are frequently driven by avacuum pump and the auto -pilot and de-icing systems by low-pressure air.

The advantages of using pneumatic powerare as follow. No return pipes are requiredas the air is discharged to the atmosphereafter the required operation has been com-pleted. A pneumatic system is light in weight,the operating fluid does not cost anything andcompressed air can be conveniently stored inhigh-pressure bottles.

DisadvantagesThe disadvantages are, first, the com-

pressed -air bottle is extremely vulnerable(especially in military aircraft), as if it is hitand punctured the bottle is liable to breakloose from its mounting and cause a great dealof damage ; secondly, leaks are more difficultto trace than when hydraulic power is used,thus increasing the maintenance difficulties ;and thirdly, it cannot be used for operatingthe retracting mechanism for undercarriagesdue to the very high pressures required.

A typical compressed -air system is illustratedin Fig. r, in which the main components areshown in their relative positions.

The compressor is mounted on and drivenby the engine of the aircraft. The pistontype is generally used and absorbs, as a rule,less than r h.p. when operating at normaldelivery pressures. It is important that thecompressor be mounted so that maximumcooling is obtained, as excessive temperaturesmay be reached if adequate cooling is notprovided. A duct is often fitted to the enginecowling to direct a cooling stream of air on tothe compressor fins. Very little maintenanceis required, and beyond an occasional lubrica-tion a well -designed compressor should func-tion for a considerable period before anoverhaul is necessary. An automatic reliefvalve is fitted so that when the, required

pressure has been attained the air passingthrough the compressor is circulated back tothe crankcase. It is important that the oilsupply in the compressor is maintained at thecorrect level, otherwise the pressure will drop.

The Oil SealThe next item of equipment is the oil seal.

This consists of a metal container with fromhalf to one and a half pints of oil throughwhich the air supplied by the compressorpasses to the delivery pipe at the top of theoil seal. A cock is also fitted to allow surplusoil to be drained away. The oil seal preventsthe air escaping back to the compressor whenthe required pressure is reached.

An oil ,trap is fitted immediately followingthe oil seal to drain off any oil which has beenforced past the baffle in the oil seal. This isnecessary owing to the effects of oil upon -anytubber tubing which may be fitted. Thecompressed -air bottle stores the air at appioxi-mately zoo to 400lb. per sq. in. A connec-tion is usually fitted to allow the bottle to becharged from an external source when theaircraft is on the ground, i.e., the engine neednot be run to charge the bottle to the correctpressure-.

The air flows from the storage bottlethrough an air filter to a pressure reducingvalve. The function of this valve is to reduce

the air pressure to the figure required tooperate the service. Tl'e operating pressurevaries from so to zoolb. per sq. in., accordingto the force required.

Triple Reading GaugeIf the brakes are operated pneumatically, a

triple reading gauge is fitted as shown inFig. r, to indicate the pressure in the circuitbefore passing through the reducing valve

Storage Bortie

Triple Gauge

AnFilter-

Oil lSeal

Tap

Reducing Valve

Jack Valve

..Fig. 1.-Diagram of a typical compressed-

di,cystent as used on modern aircraft.

and the' pressures in each of the pipe linesconnected to the brakes.

Control valves are fitted to allow the air toflow to the appropriate service. When it isrequired to operate the brakes a lever, usuallypositioned on the control column, is depressed,permitting air to flow through the brakepipe lines. To allow adeqnate manoeuvra-bility whilst taxi-ing on the ground, a specialvalve is connected to the rudder bar. Whenthe pilot pushes his right foot forward, i.e.,when he wishes to turn to the right, the valve

allows air to flow to the right wheel brakeonly, thus leaving the left wheel unbrakedand causing the aircraft to turn to the right.When the rudder bar is in the neutral positionfor straight movement, air is admitted to bothbrakes if the control lever is operated. Theamount of movement of the rudder bar alsocontrols the amount of air admitted to thebrakes, thus controlling the degree of braking.The brake shoes are forced against the brakedrum by the air expanding the tube to whichthe shoes are attached. Pneumatic brakesallow more sensitive control than whenhydraulic power is used owing to the fact thatair is compressible and hydraulic fluid is not.

Instrument

Gouge

Fig. 2.-Diagram illustrating- a typicalOacuum system.

Venturi /4'

ControlPellet Valve Valve

Pump

If a jack is incorporated in a pneumaticsystem, the air forces the piston down thecylinder in a similar manner to the way' inwhich a hydraulic jack operates.

The piping usually consists of aluminium tubing, and where flexibility is requiredarmoured rubber hose is used. Rubber'sealing rings arc fitted to the pipe connectionsto prevent leakage. Leaks may be traced bybrushing the pipes with soapy water, thepuncture being indicated by air bubbles.

De-icing EquipmentWhen pneumatic power is used to operate

de-icing equipment, the compressor suppliesair to a distributing -valve which allows theair to flow into rubber tubes fitted along thewing leading edge. The tubes are inflated anddeflated by means of the air pressure, thuspreventing ice forming or cracking ice whichhas formed before the de-icer is put intooperation. The leading edges of the fin,tail plane or aerial masts may also be pro-tected by this method.

Vacuum pumps are fitted to drive the blindflying instruments. A vacuum of approxi-mately 4in. of mercury is required. Venturitubes were originally fitted to obtain a suction,but are now being superseded by vacuumpumps, which are more reliable. Otheradvantages possessed by the pump are freedomfrom icing (the Venturi is liable to chokingby ice), and the fact that the vacuum ismaintained at low airspeeds or when taxi-ingalong the ground prior to taking off. Theinstruments indicate the attitude of theaircraft by means of a gyroscope and thesuction pump draws air into the instrumentcase through a jet which is directed on to thegyro vanes, thus operating in a similarmanner to a turbine. The rate of revolutionis fairly high, being approximately ro,000revolutions per minute. The pumps arcusually of the rotary sliding vane type andas well as supplying a vacuum may also supplyair under pressure from the exhaust. Thislatter supply may be used for inflating thewing de-icers mentioned in a previousparagraph, as only a low pressure isrequired.

Vacuum SystemA typical vacuum system is illustrated

diagrammatically in Fig. 2. In this layoutboth a Venturi tube and a vacuum pump arefitted. Should the engine fail, the pumpwould not function and the Venturi tube isfitted to operate the instruments in the eventof any such emergency.

It is necessary to install a vacuum reliefvalve in the system so as to prevent excessivevalues of vacuum which will be caused byhigh air or engine speeds. If the Venturiis located in the slipstream of the propeller,the air velocity will be greater than that ofthe aircraft itself.

A vacuum gauge may be fitted to indicatethe height of vacuum being supplied, or ifthe gauge itself is not installed a coupling isprovided so Oat a gauge may be attached forchecking purposes co tilc ,g,rond.

In conclusion, from the -a -hove shoitdescription of the use of pneumatic power inaircraft, it will be seen that its use is confinedchiefly to operating brakes, wing de-icers andinstruments. It is likely that hydraulic powerwill supersede pneumatic power for theoperation of brakes in order to reduce thenumber of systems installed in the aircraft,but the gyro -operated instruments willremain pneumatically driven.



TILL MONTH IN THE WORLD OF

Science and Invention

Grass EatersMR. GUSTAV J. MARTIN, of New

York, has 'devised a plan to feedparatroops and other " isolated forces " ongrass, leaves and wood. He told a Nev Yorkmeeting of chemists that men would have tobe " conditioned " to the diet by a course ofharmless bacteria, taken in the form of aliquid " tasting like chocolate syrup."

--aaciArs"-A Balloon Rescue MarkerMEMBERS of the U.S. Naval Air Base

at Lloyd Bennet Field, Brooklyn,N.Y., are conducting experiments with aballoon type rescue marker which could becarried in compact form by Navy pilotsengaged in over -water manoeuvres. Thedeflated balloon is attached to a cartridge inwhich is contained helium under pressure.This is attached to a band around the pilot'sarm. In a forced landing the pilot pulls thecartridge trigger, shooting the balloon aloft.

Device for Hose -pipesMR. FRED MOORHOUSE, of Hudders-

field, has recently patented aninvention that will be of interest to all firemen.It is an apparatus for supporting a hose -pipe.The hose -pipe is arranged in such a way thaton being run out it is laid quite straight.The time taken to run out a 65ft. length isfrom four to five seconds. As the usual time isfrom i5 to 20 seconds the worth of theinvention can be appreciated. In fire -fightingspeed is all important. Usually three men arerequired to run out a hose -pipe, but this newmethod requires only two-one to turn onthe water and one to run out the hose -pipe.

Warships With-out Funnels

T° provide morespace for guns

and aircraft equipment(including catapults),naval architects areplanning battleshipswithout funnels.

Huge ElectricStator'

THE largest electricstator ever to be

transported in Britainhas recently completeda successful journeyfrom the north-eastto the Midlands. Ittravelled on anL.N.E.R. transformerwagon set running

A new American warmedal .being examinedunder a magnifying -glass after it has leftthe press, z,000 ofthese medals are to bestruck for distinguishedservice in the U.S. Army

and Navy.

on 4o wheels. Weighing 130 tons andcapable of generating 50,00o kilowatts, thehuge bulk of this power -unit monopolisedthe track, completely blocking traffic on theopposite or adjoining lines.

It is to light and heat a big town, and toturn the lathes of war.

Seeing Through SteelTT is renorted from New that Feittl,

Xsccrnregacrrttrre it cannot X-raysteel plates over Bin. thick, is building anew gigantic machine to determine deepersecrets_ as part of the war production effort.The principal parts of this super -detective, ahuge electro-magnet, will weigh 125 tons,and be composed of more than too,000 piecesof silicon steel.

Its hollow glass core will toss electronsabout 800 miles, whirling them around aquarter of a million times in 1:21., of asecond. The giant machine will be housed in abuilding with 3ft. concrete walls. The operatorwill stay outside in a control room and peerat the machine through a periscope. Thewhirling electrons will strike a target togenerate a beam of highly penetrating X-rays.The beam will emerge from the machinetogether with scattered high-speed electronscapable of penetrating tin. of steel. Thecapabilities of the new tool are not yet known.

Cargo SubmarinesACCORDING to Senator Lee, the

American Army and Navy have proved" receptive " to proposals to combat theU-boat menace by sending Allied cargoesunder water by huge submarines. The cargosubmarine proposal comes from the veteraninventor, Mr. Simon Lake, whose work indeveloping submarines is known throughout

the world. He put forward the design whichhe completed in its essentials years ago fora 7,50o -ton cargo -carrying model, the firstof which he claimed could be completedwithin six months, after which shipyardsanywhere could turn them out.

Gas -driven ShipsNGINEERS in Britain are interested in

the progress made in Scandinaviancountries with gas engines for tramp steamers.The gas is produced on board from ordinarybunker coal, and is preferable to oil forBritish tramps. The latest gas engines occupyless space and consume 20 per cent. less coal.

New Welding' ProcessmR. C. W. BRETT, a well-known

authority on welding, announces anew welding process which consists ofwelding together totally dissimilar metals.He states that it is too early as yet to predictthe full extent of application. He promisessurprises, however. At first it was possibleto weld only cast and malleable iron to steel,but now any commercially applied metalscan be united in this way," he asserts.

Machine for Copying TemplatesTHE Eastman Kodak Co., in collaboration

with the North American Aviation Co.,have produced an X-ray machine for duplicat-ing templates. Its purpose is to make photo-graphic reproductions of templates bothaccurately and quickly, and the size of themachine is loft. long by 5ft. high. The'operation may take as little -as half an hour,while the print of the template can be useda quarter of an hour after developing. Theoriginal template is coated with a fluorescentlacquer (that is a lacquer which glows whenexcited with light of a particular wavelength),and an Eastman Matte film is then appliedto the surface of the template, on top of thelacquer. X-rays are then allowed to fall onthe film, which is deposited in a large chcst-like compartment, which tisimilar to fac.116":gram in anr_learant,ee. _rue ntrn WtiretiTtrii;"6edbit curea,- after which it is stored.Both positives and negatives may be made inthe apparatus.

Portable Sound LocatorTHE Army Signal Corps of the U.S. have

approved a small portable sound locatorfor aircraft, which can be slung like a camera,being not much larger. The spotter wearsheadphones to which is attached a paraboliccondenser or sound collector. This collectoris. coupled with the amplifying circuit housedin the container slung from the spotter, andleads run from the container to his headphones.The approaching aircraft is heard as a fainthum in the earphones, and the spotter turnsslowly until the noise is at a maximum, whenhe should be facing the direction from whichthe aircraft is approaching. This enableshim to put up his binoculars to the right areaof sky, instead of searching widely.

Defying GravitySOMEWHERE in New Jersey the Wright

Aeronautical Corporation are erecting anewly developed type of concrete buildingwhich can be set up more rapidly than theusual structures of steel and wood. Thisremarkable factory is being built-impossibleas it seems-from the roof down, with thefloors as the final units to be completed.


56 November, 1942NEWNES PRACTICAL MECHANICS_:,,,rmumagarr.

Inside the pressure chamber at a submarine training schol.

America's New TankTHE feature of the new American heavy

tank, Mark IV, is its revolutionaryfire power. It mounts a 75mm. cannon ina revolving turret which turns the full circle.

New System of Road DressingANEW system of road dressing is now being

used in Sheffield which is entirelyautomatic. A high -viscosity tar is appliedhot to the road surface by means of mechanicalbrushing, and is followed by a dressing ofgranite chippia§ applied difda fil5M

inlichine, which carries five tons ofmaterials. The chippini; are then rolledwell into the surface. That the new processis speedy is proved by_the fact that 9,000square yards were dressed in ?Alm. , In -addition two gangs of 12 men did the workin less time than it took four gangs, composedof larger numbers, in pre-war days.

Jack -in -the -Box " MineTN order to beat enemy engineers' mine

detectors, the Allied Forces are nowsuccessfully using a " jack-in-the-box " minewhich springs up out of the ground andexplodes. The working of the mine is asecret and so far German technicians havefailed to discover it. Th.o only informationavailable regarding them is that they are laidfor various purposes. Some mines explodewhen run over by a tank and others whentouched by a soldier's feet. Both British andNazi engineers have been using the " broom-stick " detector, but the new mine counterselectrical detection. As the engineers exploreminefields with their detectors, the new mineexplodes up out of the ground with onedetonation, then bursts and kills the engineers.

Sugar from PotatoesA CONSULTANT scientist attached to a' big international sugar manufacturingfirm has foi the past two or three years beenworking on a hunch of his own. He knew thatsugar could in some way be extracted fromthe starch contained by potatoes. He hasnow discovered how it can be done. The new

sugar -practically. indistinguishable. from th.scane sugar-is to be put into productionshortly. It should be available very earlynext year, as no new machinery is requiLscl.The potato sugar is to be made in lump,granulated and liquid form, and will be cheap.

Coal from " Slurry IfA PROCESS is now being examined by the

Coal Industry Fuel Efficjency Coni-mittee for utilising " slurry "-the part ofcoal left over after it has been washed=aS -solid fuel. At present most of this slurry xmerely dumped, or is washed down to thesea in rivers as coal dust. It is estimated thatapproximately i,000,000 tons of solid fuelcould be recovered if the process should proveefficient. Slurry is not a first class fuel, butcan be used for many purposes.

Torpedo -proof ShipIT was recently revealed by President

Roosevelt that American shipbuildingenaineers have designed a shallow -draughtcargo ship which it is hoped will be virtuallytorpedoproof. It is understood that the newvessel, riding high out of the water, will usepetrol engines, is cheap to build, and can bemass produced. It will be a small type ofship suitable principally for coastal work.'But it is hoped that larger ships will thus beset free for deep-sea work. Washingtonofficials are cautious in their claims and pointout that the new type of ship may he followedby new types of torpedoes to deal with it.

The_ Combined HarvesterDetails of a

TN order to speed up the gathering of the" corn haryests this year, the Ministry ofAgriculture state that over 1,20o reaper -threshers, or combine -harvesters were usedin this gigantic task. The combine harvesteris really several machin s in one 4n.4tractor-clirWirioun a eld- it cuts, threshesand delivers the grain in one operation. Themodern machine shown on this page how-ever, propels itself.

Dry weather is essential to get the most-etketlye...tme from these machines, though aiittM dairM:Siglhe crop -is obviated, by_t4iuse of a drying niaairie which works in con-junction with the harvester.Progress over too Years

That we have made tremendous strides in

6A-'61Ne sITUATED BEN/N© DRIVERopeRArwc GUTTER, THRESHER

coNveroA, MECHANISM

LOCATION OFTHRESHING APPARATU'

Machine Which Cuts, Threshes, and Delivers theGrain in One Operation

the harvesting of corn during the past tooyears is evident from the fact that whereasin the days of the scythe and flail it tooknearly fifty days to harvest and thresh anacre of rain it is now poksible to do th,.,c job,ill- tfiTlf hour- witr the combinedharvester.

These machines can deal with 12 to 15acres a day provided the weather is good, andconsume a gallon of petrol per acre.

The self-propelled machine illustrated,wttich is pnethe largest types, has a cuttingsweep of.

2ITha-Neitra - pours the

threshed grain into l 6o bushel tank, whichthen transfers it into -a truck which takes itoff the field to be dried.

,,RAIN FED FROM HEREINTO 7ANK OF 60 eliSHECA PACT

CRAIN DISINARGEDFROM HERE En".SPIRAL L.-rim/Er-ore

:JEPOS/TED`FROM REAR ASMACHINE PROCkED

A diagrammatic drawing showing the working of the combined harvester.



Black-out Control of L017111/0

IHE necessity of maintaining a strictblack-out during hours of darkness is asource of much inconvenience to the

average householder. The' present period ofshortening days and longer nights is, perhaps,a suitable time to discuss methods for minimi-sing this inconvenience, in preparation for thecoming winter. The greatest difficulty is experienced in

preventing light spillage from entrances anddoorways and, no doubt, the reader is onlytoo familiar with the awkward and unwieldylight traps which have become part of our

I.-O4'40....-...Oformal Door

witch Switch

Lamp

NFig. r. Complete black -out is obtained with

this system. It is not recommend -2d.

daily life. The only alternative has been themanual switching of the lighting before anexternal door is opened.

For normal household use, and for use inmany other premises, the easiest and mostconvenient way of preventing light spillage isby means of a door -operated switch, soarranged as to extinguish the lighting, or

CIO SwitchL

NbrmelSwitch

AuxLamp Lamp

Details of a. Simple Switching ArrangementBy G. F BROWNE

3: DimmingPartial extinction, or dimming, of the main

lighting appears to be the most useful method,possessing all the advantages of the othermethods without their disadvantages. Itcan be effected by means of a simple on -off "door switch with a resistance, or choke,connected 'across its terminals (Fig. 3).When the door is closed the resistance isshort circuited by the switch contacts, allowingthe lamp to receive its full working voltage.The opening of the door, and consequentopening of the switch, places the resistance inseries with the lamp, so reducing the voltageavailable at the lamp. By suitable choice ofthe value of the resistance or choke the degreeOf illumination can be reduced to any desiredlevel.

If A.C. mains are available it is desirable touse a choke rather than a resistance, becausethe heat generated by a resistance may causedamage to furnishings. or if not properlyprotected it may constitute a fire risk.

Another advantage possessed by thissystem is that at all times some current isflowing through the lamp, maintaining thefilament above ambient temperature. Thecurrent surges which occur at switching on,due to the lower resistance of the filamentwhen cold, are thus minimised, and thelife of the lamp is prolonged.

A variation of this system is to connect aneon lamp, such as the Osglim, across theswitch contacts instead of the choke (Fig. 4).As the 'resistance of the filament ramp isvery much less than that of the neon lamp,the latter will glow at almost its full brightnesswhen the door is open.

Fig. 2.-A better- arrangement, bat wiring isslightly more complicated.

reduce it to a safe level upon the door beingopened. The difficulty and inconvenience ofnegotiating a light trap, or of manuallyswitching off the light every time a door isopened is thus disposed of.

There are three ways in which the desiredeffect can be achieved.r. Complete Black -out

The automatic door switch can be arrangedto completely black -out the lighting upon everyoccasion that the door, to which'the switch isfitted, is opened. This is the simplest method,requiring a plain " on -off " switch in serieswith the normal switch (Fig. t). But theshock to the nervous system of a person in aroom which is suddenly blacked out is verygreat, and many accidents have resulted fromthis cause. For this reason, the simple" op -off" automatic door switch is netrecommended, and should not be used.

2. Subdued Auxiliary LightingThe disadvantage of the pre.viouslv

mentioned system can be disposed of byarranging the door switch as a change -overswitch (Fig. 2). When, the door is opened themain lighting is switched off, and a suitablyshaded low -power lamp is switched on. Bythis means the room is never completelyblacked out, a very low value of illuminationbeing maintained even while the door is open.

The disadvantage of this system is, ofcourse, that it increases the amount ofwiring that has to be installed, with theconsequent increased difficulty in arrangingto conceal it, or at least make it unobtrusive.

Operating Rod Spring

or,V.1.15.164.14.95.159.V.I 1,56 . H., AO, Medel

Contacts Ebonite Sheet

-Fie.- 5-A simple and effective type of dooroperated switch.

Door SwitchesThe construction of suitable door switches

is described in detail, as the problem presentslittle difficulty for the average amateurmechanic.

SwitchArchitrave

Switchoperating bar

-Fig. 6.-Mounting the switch and its operatingbar. The whole assembly can be neat and

unobtrusive

A simple type of switch is illustratedin Fig. 5. It consists of a pivoted brassbar about Six. long carrying a contact at oneend, and is spring loaded at the other, so thatthe switch is normally open. The assemblyis mounted on a sheet of paxolin or eboniteto which a further contact is secured inalignment with the moving contact. Theswitch is enclosed in a metal box, operationbeing effected by means of a short rod ofebonite, or other insulatIng material, fastened

Choke

LaoNormalSwitch

N

Fig. 3.-A satisfactory dimming circuit for meon A.C. supplies.

to the brass bar and projecting through anaperture in the container.

The completed unit is mounted on the topjamb of the door and the switch is closed,when the door is shut, by a piece of iron bar,about sin. by Kin., fastened to the door,and in line with the operating rod (Fig. 6). .

DoorSwitch

DoorSwitch

NormalSwitch

Lal7p

Neon Lapp tamp

Fig. 4.-An alternative to Fig. 3. The neonlamp replacing the L.F. choke.

There are several commercial types of switchwhich are suitable for the purpose, andamong them is the Burgess micro -switch,which is useful when concealment is import-ant, as it is so small that it can be recessedinto the jamb of a door and remain almostunnoticeable.Resistance or Choke

The resistance used should be of a highenough value to reduce the illumination to asatisfactory level, without allowing any lightto show outside the premises. A value ofabout 1,30o ohms with a rating of 25 wattsis suitable for use with a 23o -volt 6o -wattlamp, 'or 8o0 ohms rated at 4o watts for a230 -volt too -watt lamp.

The resistance need not be mounted directlyalongside the switch, but can be mounted insome unobtrusive position, if so desired, andconnected by leads being taken from it tothe switch contacts.

Where A.C. mains are available, a choke ispreferable, as previously mentioned. Thisshould have an inductance of 4 henries and becapable of carrying .1 amp for use with a230 -volt 6o -watt lamp, or 2.5 henries and .2amp in the case of a 230 -volt too -watt lamp.Installation

When installing a device of this natureit is important to ensure that the switch isconnected in the.live, or unearthed, lead. Ifthe necessary wiring alterations are carriedout from the wall switch, this condition willbe automatically met with, provided that theoriginal installation has been properly carriedout.



Bakewell's Facsimile TelegraphIt was to be expected that when Messrs.

Cook and Wheatstone invented the electrictelegraph, in. 1838, someone would not be farbehind in trying to send and receive theactual writing, and also drawings, known asfacsimile. It is therefore notable that in 185oan Englishman, F. C. Bakewell, invented afacsimile telegraph.

In this system, the design to be transmittedwas drawn upon the surface of a metalcylinder- with a fluid of insulating character:

The cylinder was connected to one pole ofan electric battery, and was continuouslyrevolved by a weight -driven motor. A wheel -shaped stylus rested upon the surface of thecylinder. The stylus was fitted on an arm theother end of which engaged in a worm -gear,geared to the cylinder driving motor.

Connected to the line circuit by means ofthe worm -gearing, the stylus was enabled toexplore the whole surface of the cylinder in aspiral of a certain pitch. While ,the stylusrested on the metal of the cylinder a currentpassed to the line, but when the stylus passedover a portion of the cylinder on which thedesign was drawn, the circuit was interruptedand no current, passed.- At the receiving end a cylinder revolvedsynchronously with thesending cylinder. Anink-stylo was mounted on worm gearingsimilar to the sending stylo. Normally held

Picture Tele raphyHow Photographs and Drawings are TransmittedOver Great Distances by Means of Electricity

By 'N. T. LOWE and E. PHILLIPS

away from the surfaceof the drum, which wascovered with paper,the line current passedthrough electro-mag-nets fixed under theouter end of the ink-stylo arm.

When the currentwas interrupted, theink-stylo fell on thesurface of the paper,being weighted for thepurpose, and made amark. Resumption ofthe current flow attract-ed the free end of theink-stylo arm and raisedit from the paper. Acopy of the designthus appeared on thepaper.

This system failedowing to the difficultyof keeping synchroni-sation, and the lack ofan efficient relay.

D'Arlincourt'sApparatus

Twelve years later,however, the AbbeCaselli, an Italian, pro-duced an apparatus onsimilar lines. It trans-mitted drawings and

A photograph, of the interior of St. Stephen's, Vienna, telegraphed diagrams, and workedfrom Munich to London. Note the wealth of detail. (By the courtesy on the Paris -Amiens

of the Postmaster -General.) wire for some years.Then D'Arlincourt, in

ALMOST every day you can see tele- France, came upon the scene with his- graphed pictures in the press. They facsimile telegraph in 1878, which was actually.

are mostly war pictures. You will tried in London at the Central Telegraphnotice by the accompanying photographic Office. The designs were reproduced on theillustrations (which have not been retouched) receiver in black on a white ground. Seventhat the clarity is remarkable. minutes to deal with a picture izin. by 21in.

was considered too long. By the way,synchronisation of the sending and receivinginstruments in picture telegraphy is absolutely

essential. D'Arlincourt's apparatus was foundlacking in this respect, that being anotherreason why it did not find favour at St.Martin's -le -Grand. The French Telegraphauthorities also cast it out, but after a longertrial:. To obtain perfect reproduction the sender

and receiver must run at the same speed.And until many years later (in 1919, to beexact, when the tuning fork was adapted forthe purpose of synchronisation) there wereno means of obtaining absolute precision ofmovement.

Five years before d'Arlincourt, however,the light-sensitive properties of selenium werediscovered. Thorne Baker, of England, andProf. Korn, of Germany, used selenium in anapparatus which they each invented fortranslating the light and shade of a pictureinto electric current. That is the principleupon which pictures are telegraphed, andwhich will be expMined later. -

In those days there were no efficient meansof increasing small values of current, and thelines used for transmission were, technically,not good.

A national English newspaper experimentedwith the Korn system on their Manchester -London private telegraph line, but owing tothe difficulties already mentioned, it was notUsed to any great extent.

Now, the same discovery which wasresponsible for broadcasting as we know itto -day, provided- the solution of increasingthe values of current. It is known as ampli-fication.

As is well known, Sir Ambrose Flemingdiscovered the principle of the .thermionicvalve in 1912. The modern form of thisvalve amplifies weak currents enormously.The Photo -electric Cell

Then came the - re -discovery after WorldWar No. t of the photo -electric cell, whichadded yet another contribution, in that it

- gave inventors the means for which they hadlong sought, that of turning the light andshade of a photograph into electric currentswhich could be sent along a wire. The lastobstacle to real picture telegraphy was thus

The Picture' Telegraphy' Depdrtnient of the Office. The power(witch -board is on the left, and the control panel on the right. (By the courtesy of

the Postmaster -General.)


November, 1942

removed when, in addition to actual trans-mission and reception, great improvementswere made in photographic materials.

Three systems of picture telegraphy wereworking by 1926, the Siemens-KarolusTelefunken in Germany, the Belin in France,and the Bell in America. Great Britain, withits comparatively small distances between largetowns, did not offer much inducement forwork on this method of communication. Thedistances between the cities of the Continentand in the U.S.A., however, invited somemeans for the speedy transference of -pictures,and consequently the use of picture telegraphapparatus was an advantage.

The Post Office installed a set in theCentral Telegraph Office, London, for workingto the Continent, and the first public picturetelegraph service to Berlin opened inJanuary, 1930. To -day, pictures are mostlyflashed by radio, but a detailed description ofone of the line systems will be interesting.

In these systems telegraphed pictures aretransmitted over telephone circuits, andpicture transmission does not in any wayresemble ordinary telegraphy.

Sending of a picture is performed bymeans of a light-sensitive apparatus called a" photo -electric cell." This is a glass bulb,which has part of its inner surface coated witha material which is sensitive to light. Thematerial first in use was potassium ; but thishas now given place to caesium, which givesa better response to light. The metal isdeposited as a very thin film on the glags.Placed just in front of the metallised surface,and also inside the bulb, is a wire mesh orgrid.

Under the influence of light a stream of"electrons " flows 'from the caesium to the

- grid. This, in effect, is an electric currentgenerated by the light. The current is verysmall, being of the order of 4 micro -amperes

4 This small current is(i,000,000 ampere).passed to a valve amplifier and so increasedto the amount necessary for line transmission.

The picture or other matter to be tele-graphed is clipped on a metal cylinder which,by means of an electric motor, is arranged torevolve continuously in front of the photo-electric cell.

A beam of light from a spot -light lamp is - Photographic Detailsdirected upon the surface of the picture by As photographic materials are

used for reception, a fully equip-ped photographic dark room isessential. Photographic film orpaper of suitable size is clippedround a metal cylinder in tne

NEWNES PRACTICAL MECHANICS

is determined by the characteristics of the lineused for transmission.

For continental working, it is 1,424 pulsa-tions per second. Pulsations of current arethus caused through the photo -electric cell,and when passed through the amplifyingsystem these cause a carrier wave of the samefrequency.

-

. -

Siemens-Karolus TelegraphThe photo -electric cell used in the Siemens-

Karolus picture telegraph (which systethbefore the war was used in the Post Office), ismade in the form of a ring, the light passingto the picture through the 'central hole. Thelens for focusing the light on the picture ismounted just behind the cell which, togetherwith the lens system, is mounted on a screwaxle which is turned by gearing with thedriving motor.

prisms and focused by a lens. A disc witha toothed edge rotates between the light andthe picture. The light is interrupted by thismeans and reaches the picture in a series ofpulsations. The number of these pulsations

Close to the cylinder on which 'the pictureis clipped the photo -electric cell is placed.Now the picture cylinder is revolving con-tinuously omits axis, and the photo -electriccell and lens are gradually moving downwards.,As a consequence the whole of the picturecomes before -the light -spot, point by point,and the picture is " explored ' or " scanned "in this way by ,a spiral of light from top tobottom. As the light strikes the picture it isreflected into the photd-electriccell, and as the value of the lightreflected varies with the light

-and shade of the picture (a brightpatch reflecting all the light,and darker patches reflectingless light), a varying currentpasses across the photo -electriccell from the sensitive surfaceto the mesh.

From the mesh the currentpasses to the amplifier and so tothe line, where it can now bedetected, by any electric means,and, if desired, can be connectedto headphones and the picture"heard."This isheard as a burbling note similarto that which we hear on thewireless when television signalsare being broadcast.

A close-up view of the control 'Panel. The picture transmitting apparatus is seen onthe right. - (By the courtesy of the Postmaster -General.)

59

dark room, and enclosed in a light -tight case,which has a shutter. When the caseis placed in the apparatus for receptionthe shutter is opened automatically.The cylinder is revolved by a motor at thesame speed as the ,picture cylinder at thesending end, and light trona a, spot -light lainpis focused on the film by means of a lens.The method of modulating this light accordingto the, variation of the current being receivedfrom the sending apparatus varies in the sys--tern. employed. The Siemens-Karolus andBelin systems use an oscillator. This is -asmall mirror attached to a wire which passesbetween the._ close -set poles of an electro-magnet.- When -electric currents pass alongthis wire, it is twisted against the pull of themagnet, and the amount of this twist is pro-. portional to the strength of the current. So.a small current will cause the wire to waver, so to speak, but a strong current may cause atwist_ almost to right angles. As a beam oflight is focukd on the mirror itself, thesevibrations Will cause the reflection of thisbeam to move.rapidly frbrn side to side. Thisreflection, which is rectangular in shape, isarranged to pass through an opening in amask, and then is focused as a spot of lighton the receiving cylinder. The picture maybe received either as a positive or a negative ;

A fine specimen picture telegraphed fromCopenhagen to London. (By the courtesy of

the Postmaster -General.) .

the former is now Usual.. Special bromidepaper is 'used for this. For the high lights'of the picture no light is allowed to fall uponthe paper, but for the varying tones of theshadowS, the vibrations of the mirror willcause the necessary amount of light to fallon the paPer, bit by bit. As the cylinder andpaper are continually revolving in front of the

light; and the light is gradually moving down-wards; it records pOint by point and in theforth of a fine spiral, the variations of lightand shade of, the picture being sent. After

"reception S cOmpleted, Which takes about12 minutes, the cylinder with the paper istaken to the darkroom and quickly developed,fixed, washed and dried and then deliveredto the addressee in a short tine.


November, 1942

greetings have been telegraphed to and fromthe Continent.

In the United States a wide use is made ofthe picture and facsimile telegraph for com-mercial and legal purposes, and items trans-mitted through London from the U.S.A. toEurope and vice versa have included legaldocuments, -signed statements, and similarmatter, as well as news pictures.

For some years before the war practicallyevery event of importance on the Continenthad been illustrated in the daily papers bymeans of a " telegraphed picture." A largenumber of news items have also been tele-graphed from London to Continental cities.Royal weddings and political events of allkinds, railway and other accidents, and thearrivals of transatlantic fliers are among thesubjects where the picture telegraph servedthe requirement of speedy transmission.

On one occasion a photograph of an eventwhich happened on the Continent at mid-night was telegraphed to London and appearedin the early morning edition of a Londonpaper.

Wireless Photogram ServiceCable and Wireless, Ltd., send pictures

across the Atlantic by wireless. The companyhas coined the word " photogram," and thesystem is known as " The Wireless PhotogramService." Some interesting information hasbeen presented in a picturesque manner bymeans of an illustrated brochure. It is pointedout that, in sending pictures and facsimilematter across the "-Pond," at least a week issaved.

The value of this time -saving device isstressed particularly for the press, fashionartists, motor -car dealers, advertisers, archi-tects, engineers, photographers, etc. Oneparticular photogram, the largest ever trans-mitted across the Atlantic, covered practicallythe whole of a newspaper page. It was anadvertisement of an £8,000,000 financialprospectus.

Broadcast transmission of photographs bywireless was attempted by Knudsen in 1908.but only crude results were at first obtained.Later, a simple form of apparatus,invented by Thorne -Baker in 1933, pickedup broadcast pictures with a two -valve receiver.The interest of this, however, is limited.

Other systems are the " Nippon and the" Standard," but these differ very little fromthose already described. It is interesting to',note that facsimile telegraphy has been usedfor some years past between Moscow andvarious cities in the U.S.S.R.-that is, insteadof employing a mechanical conveyance, actualsheets of printed matter have been " trans-ported " by means of picture telegraphy, andby radio at that ! The U.S.S.R. has foundpicture and facsimile telegraphy of greatvalue in its immense territories.

60

Bell SystemOther systems differ from the foregoing

in the method of transforming the receivedcurrents into terms of light. The Bellsystem, used mainly in the United States,has a metal ribbon vibrating in front of asmall hole through which the light shines.The rate of vibration is affected by thevarying values of the received current, and somore or less light is permitted to pass on tothe photographic paper or film.

Used largely for wireless reception, theWright system has substantial differences.The receiving apparatus comprises a metalcylinder which is divided into two lengthsby a fine slit. Sensitive paper is clippedround this, sensitive side inwards, and isheld by a clip which moves along the cylinder,under the influence of a worm screw drivenby a motor. Ingenious optical meals, knownas Kerr cell, and Nicol prisms, are used fortransmuting the received electric currentsinto corresponding terms of light. Theresultant light is caused to revolve and shinethrough the slit in the cylinder on to thesensitised paper, which, under the influenceof the worm screw, is slowly moving alongthe cylinder, and so continually exposingfresh surface to the beam.

Picture SizesSize of the pictures and rate of scanning (or

number of lines per millimetre) are thesubject of international arrangement. TheWright system has a picture size approxi-mately tains. by 8ins., and the rate of scanIs four lines per millimetre. Other systemsproduce a picture about 8iins, by 6iirts.,and the rate of scan is 5:1, lines Per millimetre.With picture telegraphy over wires the largernumber of lines gives the finer result; butfor wireless transmission four lines permillimetre is satisfactory.

Marconi -Wright SystemA modification of the Wright system, the

Marconi -Wright, is useful for the trans-mission of actual messages. It is possible totransmit two messages, each measuring 8in.by loin., in less than 20 minutes. Messages

NEWIES PRACTICAL MECHANICS

r6in. by 4in. have been received in 4.1s minutes.Of course, it is difficult to give up-to-dateinformation at the moment, but we do knowthat in operation this apparatus ran con-tinuously. It was therefore not necessary tostop the machinery whilst . working, thepictures being dealt with in immediate suc-cession. Naturally this saved a lot of time-a valuable asset in all forms of communica-tion.

Used for telegraphing pictures over Atlanticcables, the " Bart -Lane " system differed'greatly from any other. The results showed agood range of tones, but had a rather heavy" grain." This system has now fallen intodisuse as the newer systems described aresuperior in every way. The system, however,was used on July 25th, 1920, for telegraphingpictures of the American yacht race fromAmerica to England for the daily press.Copies of the pictures were also sent by post,and on receipt of these the telegraphed pic-tures were reprinted side by side with, theposted copies for the purpose of comparison,which was favourable.Public Picture Telegraph Service

On the introduction of the public picturetelegraph service in 1930 newspapers andnews agencies were quick to recognise its

value. The first service,to Berlin, was openedby the Postmaster -General on January 7th,1930. This was follow-ed by services toFrankfurt - on - Main(Germany). on January21st, Copenhagen(Den-mark) on February20th, Munich (Ger-many) on April 25th,Vienna (Austria) onMay 20th, Stockholm(Sweden) on September4th; Rome (Italy) onSeptember 3rd, 1931,Oslo (Norway) onNovember 1st, 1931;Amsterdam (Holland)On February 1st, 1933,and Paris (France) inJune, 1933.

These services havebeen extensively usedfor pieis Ptirp5ses,and also for com-mercial and privatepurposes.

Tabulated trade re-turns, letters in extensO;engineering plans, de-signs for fashions andadvertisements, andseasonal and festive

(Above) Placing thecylinder, with photo-graph,in the transmitting

apparatus.

(Right) Clipping thepicture to be transmittedon to the drum, or cylin-der. (By the courtesyof the Postmaster -

General.)



Battery -electric BicyclesFurther Notes on Their Construction and Operation

By P. G. BOYD, B.Sc.

Couchaicd from p. 14, October issue.)

The electrically -driven bicycle described by the author.

Charging DetailsAGOOD battery ...giving its full rated

capacity is essential. The specific gra-vity of the acid should be kept up to,

but not above the maximum value permittede pby tharticular battery inanufacturer, and the

level of the acid should be kept higher thannocnal-slightly above the bottom of the fil-ling tubes. OVercharging of the battery, par-ticularly at excessive amps, when the bandyis more than half charged, should be avoided.On the other hand, trickle charging is, also tobe avoided as it tends to " form " the grids.Best results will be obtained if the battery ischarged at the maker's recommended rates,which generally are about 4% amps. for6o amp. -hour, and 7 amps for too amp. -hoursizes, etc. To avoid damage by overchargingit is best to.sazdivarily4Lop .gwging jul,

befarIlie- specific gravity ceases to risefurther, say when it reads 1.275, and aboutonce a month to overcharge at normal orslightly below normal amps. for about ,5 hoursafter the specific gravity has reached itsmaximum of, say, I.280.

The writer's battery (12 volts 57 amp. -hr.)has up to date done over 600 miles, and, sofar, shows no signs of deteriorating-in fact,the reverse is the case-it having on test at418 miles given an output of 65 amp. -'hourswhen discharged in 9 hours. From datawhich the battery manufacturers have pro-vided it is estimated that the battery wouldgive a mileage of over 3,000 with thepresent inefficient motor on the bicycle beforeits capacity falls below 45 amp. -hours. Thisis a very good life for a battery not intendedfor this type of work. It may be added thatcar starter batteries of the lead -acid type are,for weight, space and efficiency; better suitedto a bicycle than any other type kpown to thewriter. It is necessary however to maintainthem properly for this rather severe type ofworking.

Two points of interest are, first, it isunnecessary to fully discharge a car -starter(pasted plates) type battery occasionally inOrder to maintain it properly, and, secondly,it is impossible to state the extent to which abattery has been discharged from the readingsof the specific gravity alone. This is becauseof the fact that the fall in specific gravity' isproportional to the amp. -hours taken outof the battery regardless of the rate at whichthey were taken out.General Constructional Hints

Fig. 6 shows that in the case of the writer'sbicycle the full battery voltage is switched

straight on to themotor when starting;but, usually, in .order toreduce the startingcurrent, and also toreduce the stress on thefree -wheel and chain,the starting switch isnot closed until a speedof about 3 m.p.h. isattained by pedalling.If starting from rest isrequired it would bebetter to use a startingresistance: rather thantap the battery.

An old motor -carstarter switch is usedfor switching on themotor. It is operatedby a lever as direct

operation is tiresome on a long journey.For safety it is recommended that it shouldbe of the free -release or " dead -man ".type, and it should be operated by theleft hand. A locking device should beprovided to prevent the switch being closedwhen the machine is parked.

Heavy Leads NecessaryIt is very essential to use heavy low resistance

of the machine as seen from theThe three -speed switch is in front

of the handlebars.

leads and good tight connections, solderedwhere possible, in order. to reduce voltagedrop. This applies particularly if a 6 -voltsystem is used.

If an earth return is used for one of theconnections between the battery and themotor, a heavy copper connection, whichneed not be insulated, should also be used

A viewsaddle.

between the motor frame and the" earthed "battery terminal, as a frame " earth " lead isliable to have a high resistance. The voltage&bp on the separate leads, etc., may easily betested with a voltmeter with, say 2 or 4 voltsfrom the battery, and the motor's armaturelocked. In connection with this question ofvoltage drop, the ammeter which the writeruses, as shown in Fig. 6, is of interest. It hasno terminals-the insulated lead is loopedthrough an iron ring. There is, therefore, novoltage drop in the meter, and it is short-circuit -proof. This interesting ammeter,which is surprisingly accurate, is of the centrezero type. and was obtained from an old FordV8 motor -car. As it was calibrated only upto 3o amps., only half the total current is putthrough -it, and its reading is approximatelydoubled to ascertain the total current.

In the case of the writer's bicycle 3 lb. ofbattery stores sufficient electricity for onemile. It may be taken, therefore, that if 3 lb.of useless dead weight is replaced by usefulbattery weight slightly more than one mileextra per battery charge will be obtained.

Pelalling Gear and Motor DriveFor many reasons the writer decided to

retain the use of the ordinary pedalling gear.This prevents the conversion of an ordinaryMotor -cycle to electric drive, but certainmodels of the light auto -cycle type could beconverted. A free -wheel in the pow,.erwoIle, tapwhen pedalling, an Irec-wkelinggoing dtva jrl tad wfien Coming to rest.

advantage of the free -wheelcan be obtained the free -wheel -Should be inthe final driven sprocket, that is on the roadwheel hub. Both the motor and chain willthen be at rest when free -wheeling.

On the Writer's machine a heavy dutymin. free -wheel is used, and to it is boltedthel large kin. sprocket.The driving chain isa standard light in. by in. cycle chain, andthis is found to be amply strong in view of theeven torque and relatively high chain speed.Incidentally, the chain drive has proved tobe very efficient-there is only a friction lossof 6 watts in it at full speed. It is also verysilent. The driving and driven sprockets have12 and 48 teeth respectively. It is essential toarrange the motor mounting in such a waythat the chain may be perfectly aligned. Asthe chain very seldom requires adjustment it issimpler and better to use packing pieces underthe motor than to provide a jockey pulley.Effective mud -guarding for the chain isessential.

It has 'been suggested that a three -speedgear should be put in the motor drive, but thewriter prefers to obtain any speed variationsrequired electrically. It may be aided that athree -speed gear with correct ratios would beof some advantage in the pedal drive.

Limitations of Battery -electric BicyclesThe writer's experimental bicycle is reason-

ably satisfactory for his purpose, but would notbe satisfactory for daily use in inexperienbedhands. More than 5o people, both male andfemale, have driven it and they have allexpressed satisfaction with its performance,particularily its silence and simplicity, butthey have complained about its excessiveweight. With a suitable efficient motordesigned specially for the job and weighingabout 12 lb., and a suitable cycle frame,a cheap and reliable machine for short



distance transport could be manufactured.Its limitations in speed and range of aboutzo m.p.h. and 4o miles per battery chargeshould, however, be fully understood.

Unlike a petrol driven vehicle, when petrolwas available on the roadside in unlimitedquantities at about is. 6d. a gallon, and wheninefficiency did not therefore much matter,a battery -electric vehicle, because of thestrictly limited amount of energy which canbe stored in the battery, must be very effi-ciently designed in the first instance, andcarefully maintained in efficient conditionafterwards. Fortunately the maintenance ofa good electric vehicle should be very smalland their greatest disadvantage, namely, a run-down battery on the road, is largely overcomeby the electric bicycle where one may alwayspedal home.

Operating DataFinally, it is thought that other experi-

menters will be interested in comparing theirresults with the following data which wasobtained on the writer's machine before

removing the 33 lb. motor. (Other data wasgiven in PRACTICAL MECHANICS, June, 1942.)

In Fig. 5, the speed curve shows the speed,both in r.p.m. of thetnotor, and in road speedin'in.p.h. for various outputs from the battery.The various speeds were obtained by brakingon the level or going up hills. If a speedo-meter is not available the speed may becalculated accurately by counting the revolu-tions of the road wheels for a period of, say,JO sec.

With the motor as finally altefed the steepestgradient which could be clfmbed withoutpedal assistance and with a 12 -stone riderwas 1 in to.

On a level, dry concrete road three tests,which will be of interest to cycle tandem

Test Watts Steady Steady Time to reachNo. at Watts Speed Steady Watts

I Start m.p.h. and SpeedI 56o 33o 19 26 seconds2 690 36o 16 36

700 420 14 40 3)

enthusiasts also, were made. Wind directionmay be neglected as runs intwo directionswere made and the averages taken. Theresults of these tests are shown in the table.

Test No. 1 was made with only the tz-stonerider on the machine.

Test No. 2 was made with the 12 -stonerider and a I 2 !, -stone pillion passenger.

Test No. 3 was made with the 52 -stonerider on the machine and pulling another rideron another bicycle weighing a further 15 stonetotal.

The speed at start in all tests was 4 m.p.h.and the watts quoted are the watts outputfrom the battery-not the input to the motor.

Both the latter and also the h.p. output fromthe motor may be calculated from the curvesin Fig. 5, if required, for each of the threetests.

Of final interest might be the fact that theonly repairs, breakages or adjustments re-quired during 600 miles on the writer'smachine was twice tightening the motor chain.This reliability is attributed to the absenceof reciprocating parts.

Electric Clock ChimesConstructional Details of Mechanism for Operating Chimes from an Electrical Clock System

1st Quarter

[&is f d:

IP ip f/f

2nd Quarter (Half Hour)f 1 s f s 1 f:

3rd Quarter1 f s d: d I f: 1

w ell

J6-i 0 .c W 0 I

4th Quarter (Hour)flsd f SI4 ID_

f: 1 is s d

dB

S=r

f

C=5

Fig. 1.-The popular

rl recently reprinted the articlesWdesCribing a Master and Slave clocksystem (see January, 1942, and

October, 1942, issues) and in response to therequests of many readers we reprint the articleon a suitable chiming mechanism, which wasfirst published in the September, 1934, issue.This mechanism is not quite such a simplematter as would at first appear, owing to thefact that it is almost essential to call inthe aid of clockwork in order to govern thestrikers. The reason for this is that theonly alternative is a motor which would turnthe necessary governing roller, and apartfrom the power required for the motor,the necessity for selt-starting irises. Themaster clock operates through the power ofa three -volt dry cell, and it is almost impossibleto find a satisfactory self-starting motorwhich would operate from this voltage, andthis means that a separate supply wouldbe required for the motor, with the addedcomplication of some separate switching to beoperated at the chiming periods. Beforedealing with the construction of a suitablemechanism, the principles will first be de-scribed.

Westmis star Chime s.

The Chimes There are in use in England several musical

sequences known as chimes, some of which

Fig. 2.-How to suspend

are only popular in the district in which theyare heard, whilst others are of almost universalpopularity. The Westminster (or Big Ben)chimes are undoubtedly the most popular,and probably the simplest to construct fromthe amateur clockmaker's point of view.Residents of Portsmouth probably prefer tocall this particular combination the Pompeychimes. There is also the Cambridge com-bination, and others which are less known.The Westminster consists of forty notes inall, divided up into ten separate peals or com-binations, each of four notes. If the majorityof people were asked tg_luirn these chimesthey would be found to offer differai versionsof the quarter, half and three-quarter intervals.They do not each commence in the samesequente, but. are varied, and to any musicalear it is obvimis after hearing each peal justwhat part of the hour is beiiiirtung, al there isa musical arrangement in the peal which jiveseach chime a completeness, somewhat afterthe manner of an ordinary sentence inEnglish. Thus, when the first quarter ischimed it expresses finality gnly f9

a tplacillriaTi em t f thechimes in Fig. r is carefully studied it willbe seen how the peals vary. It will be obviousthat only four separate notes are required,and in most striking mechanisms these four

the chime tubes to prevent undueimpairing the tone.

movement without



Fig. 3.-Method of constructinga support for chime rods.

notes are struck together to form thehour -striking note. In ,more elaboratemechanism a separate note is employed, aswith the actual Big Ben system. Thisarrangement will necessitate a separate contactand other complications which may not beconsidered worth while.

Rods or TubesFor the actual notes metal rods or tubes are

usual ; the rod enables a more compactarrangement to be constructed, but thetube gives a much more pleasing tune andenables deeper notes to be obtained. Brasswill be fotmd quite suitable, and if rod is tobe employed it must be clamped at one end,a satisfactory arrangement being depicted inFig. 3, where a piece of ordinary broom -handle is cut down the centre after four holesare drilled transversely to accommodate therod. Tone will be improved if thin leatheris placed between the wood and the rod,and the notes may be adjusted by slidingthe rods through after tightening the nutsto hold the rod moderately firmly. A pencil orany piece of wood will enable the rods tobe struck whilst adjusting the notes. Fortubes a hole should be drilled slightly belowone end and pieces of gut (a violin or banjostring will be found admirable), loopedthrough, as shown in Fig. 2. It will be seenthat in addition a strip of wood should bearranged a short distance below the suspensionpoint, and small block of wood shouldextend between the rods and be joined to asimilar strip on the other side of the rods.Felt glued to the surface of these woodenpieces will prevent undue movement of thetubes, and will prevent movement due tovibration, without impairing the tone whenthe tubes are struck.

The Operating HammersThe cleanest tone will be obtained from

leather -tipped hammers, and one of the easiestmethods of constructing these satisfactorilyis to take a piece of brass rod Dn. indiameter. This is cut into in. lengths, andone end of each length is bored out to l in.diameter by lin. deep, and into this is forceda piece cut from a leather lathe belt (roundsection). This is hammered lightly into therecess in the brass hammer, and furnishes amost useful striker. A transverse hole toaccommodate a piece of zo-gauge piano wire,and a tapped hole to take a locking screw,enables the hammer to be fitted to the strikerand to be 'adjusted to provide the correctblow. ADetails of this are given in Fig. 4.When mounting the hammer the wire shouldbe bent, so that in the position of rest thesurfacs of the Icathef js slightly acsis .21 t_bgrod or tube, and when hilted the weight willbe sufficient to enable the hammer to give therequisite blow to the rod pr tube, and thenjump clear. This adjustment may easily bemade clear after assembly.

Direct or Remote ControlWe now arrive at the point where we have

to decide upon the method of operating the

chimes. The advantage of the electric clockis that the master may be stowed away in acellar or attic, and slaves operated at anydesired position. In a similar manner thechimes may be placed in any desired positionand operated from any slave. To preserve aneat appearance the chiming rods may bemounted in a small cabinet with electro-magnets for striking, and these may becontrolled by the striking mechanism arrangedin some other position. Alternatively, thestriking mechanism may consist of ordinaryclockwork gears with the hammers raised andreleased by pins on a drum, and this gearingmay be set free by electrical means at adistance. Fig. 5 illustrates the two methodsdiagrammatically, and it will be seen that thesecond method offers the simplest solutionand is by a great deal the cheaper. Onemagnet only is required, and this will releasethe rotating drum carrying the pins which raisethe hammers.

/stQuartet {

Half_Hour

ThreeQuarter

Hammers orContacts

ig. 6.-To mark on thechime -operating drum a stripshould be marked off is thismanner and then wrapped

round the drum.

.

For bothmethods it isnecessary to.mark out thedrum or cylinderwhich carrieseither pins tolift the hammersor pins to makethe contacts tooperate themagnets to liftt h e hammers.In general, alarge diameterdrum will beneeded, as thisnot only facili-tates the inser-tion of theoperating con-tacts but reduceserrors in settingout. For this itis necessary t omark out thesurface of thecylinder in theto separate pealsmentioned in thefirst section. Aspace mustseparate eachpeal, that be-tween successivequarters beingslightly greaterthan betweenthe individualsections of eachpeal. A speci-m e n marking -out strip isshown in Fig:6, from which it

will be seen that 4o pins have to be insertedto agree with the notes in Fig. 1. Thestrip should be of the same size as the

brass Hoddrilled to take leather

LockingScrew

F

Hole toaccomodate20 G Piano Wire

Piece from f"leatherlathe belt

Fig. 4.-The simplest method of constructing achime hammer.

circumference of the drum which is used,and it should be wrapped round the drum,and holes drilled at the points which aremarked, or, alternatively, nails may be driveninto the wood. For the direct operation of thehammers tin. wire nails will be suitable, butfor operating the contacts gramophone needleswill be found more suitable on account of theirshortness and rigidity.

Sufficient has been written to enable theamateur clockmaker to build a completeelectric chiming mechanism, and furtherconstructional details are purposely not in-cluded as it is possible that each constructorwill desire to assemble the apparatus to suithis individual requirements. A word of advicemay be given before closing, and that is, useat least an eight -day clock mechanism for the

Soft IronHammer Armature

ChimingRod

Hammer

Pikot

ChimingRod

Contact makingmechanism (Clockwork

operated)

To SksveClockcontacts

Hammer operatingrod driven byclockwork

Fig. 5.-Two methods of arranging the chimingmechanism.

striking gear, or the continued rewinding ofthis part of the clock system will detract fromthe advantages of the electrically -operatedtimepieces.

Books ReceivedHammer and Nails Carpentry. Pub-

lished by Evans Brothers, Ltd. 54pages. Price- 3s. net.

THIS useful book is intended for theA handyman or householder who likesmaking' things in wood, but who has hadWk. p_2paining in woodwork. The bookexplains, with itrald Of TiTilte76Ug 111111Tilztions, how to make useful articles for houseand garden without having to cut difficultjoints. Simple constructional details of awide range of domestic and garden fitmentsare given, including, amongst other things,fixing shelves, poultry pens, small green-.'house, tool shed, folding cot, light table,garden cart and a handy ladder. If you are

one of the many householders who are handy,with a hammer and nails this is just the bookfor you.Problems in Radio Engineering. By

E. T. A. Rapson, A.M.I.E.E. Publishedby Sir Isaac Pitman and Sons, Ltd.i5o pages. Price 5s. net.

THE problems given in this book, which isa fifth edition, were collected and

classified to facilitate the class -Work in radioengineering gt §outkall Technical College.They are drawn froin faSE ekartinatir_snpapers of the City and Guilds of LondonInstitute and other Institutions, the problemsembracing such subjects as electrical com-munications, radio communication, and tele-graphy and telephony. Descriptive exampleshave been included as a guidance for privatestudents.


64 NEWNES PRACTICAL MECHANKS November, 19.42

The Story of Chemical DiscoveryNo, 16.-The Science of Synthetic Drugs. Chemistry's Contribution to the Medical. Art

TO modern chemical science mankindowes, if not the complete and per-manent conquest of pain, at least the

efficient alleviation of that universally dreadedfoe of humanity.

In ancient times, physical pain was, in somemeasure, successfully stifled by the use ofcertain herb decoctions, consisting mainly ofopium and opium -like extracts. Right upto living memory, medicine depended, withone or two exceptions, for its pain -relievingmethods upon the various root, bark andplant extracts which had been known forcenturies. The first step in the elucidationof the active principle of a typical pain -deadening drug was taken in 1803 by theFrench chemist, Derosne. This workerobtained from opium (which is essentially thedried juice of a species of poppy) a crystallinesubstance which he termed morphine ormorphia (from the Greek Morpheus, the godof dreams). This extracted material hefound to possess the same properties as opium,but in an intensified degree.

Derosne's discovery was little heeded atthe time, and so was a similar and independentdiscovery which was made a few years laterby the German druggist, Set -tin -net.

In 1818, two French chemists separated thedrug strychnine-one of the most deadly ofpoisons-from certain tropical seeds, and ayear later they obtained another similarpoison, brucine, from the same source.

Then followed the extraction of quininefrom cinchona bark. Quinine, strychnine,brucine and similar extractive substanceswere termed alkaloids owing to their feeblyalkaline character. At the present time,about two hundred of these plant alkaloidsare known. Most of them are powerfulpoisons, but they are not all medicinallyvaluable.

Use of AlkaloidsWith the coming of the alkaloids, medical

science endeavoured to formulate a newsystem of controlling pain and disease. To acertain extent this system succeeded, and,with modifications, it has survived even atthe present day. We use morphia to -dayvery extensively on account of its specificpain -killing propensities, yet we still relyupon the poppy plant for our supplies of thisvaluable drug. Quinine has never beensynthesised or prepared artificially. It isone of the drugs which has so far defied theefforts of chemical science toproduce it in the laboratory.Likewise, the mixture of alkaloidswhich occur in the foxglove plantand which go under the nameof digitalis have not been madeartificially. .Yet digitalis is anindispensible drug for use by theInedical practitioner in dealingwith heart cases.

Chemical science seems firstto have attacked the syntheticdrug question by concentratingupon pain -killing substances.Probably the first artificiallyproduced pain -reliever was the gasnitrous oxide (originally called" laughing gas "), which was dis-covered at the beginning of the lastcentury by the British chemistand experimenter, Sir HumphryDavy. Davy found that when hebreathed this gas it gave rise toexcitement (hence the name" laughing gas "), followed by atransient insensibility. Nitrous

oxide is readily made by heating ammoniumnitrate, and to this day this medium, thepioneer of artificially produced pain -deadening agents, functions daily in countlessdental surgeries as the " gas " which isadministered for the more difficult andprolonged of dental extractions.

Then, towards the middle of the lastcentury, came the use'of chloroform and etheras anesthetics. Ether seems to have beenknown for centuries, but it was apparently

Adolph von Barer, German chennst, Oro firstsynthesised' many important drugs.,

never used as an anesthetic until' it wasintroduced for this purpose in 1846 byMorton, an American doctor.

ChloroformIn the following year Sir James Simpson

demonstrated the valuable anaesthetic pro-perty of chloroform. At. that time chloro-form was almost an unknown substance. Ithad first been made in 1831 by Baron Liebig,the German chemist and the introducer ofour present-day meat extracts, Liebig obtain-ing impure chloroform by distilling bleachingpowder with acetone.

To this day, enormous amounts of chloro-form are manufactured on the large scale in

Acetic acid being produced -as a laboratory experiment. Such a3acid underlies the formation of ninny drugs of the" aspirin" type.

the same way, or by distilling purified alcoholwith bleaching powder (chloride of lime).Chloroform is one of the most valuable -materials which chemistry has ever given tomedicine. The coming of chloroform, whichis a typical synthetic material, at once over-came for thousands the- appalling terror ofhaving to submit to a major operation.

It had long been known that the natives ofPeru made a habit of chewing the leaves of acertain plant when they were about to undergoprolonged exertion. They employeddecoctions of these' leaves as pain -killers also.

Discovery of CocaineIn 1860, Neumann, a German chemist,

obtained a supply of the Peruvian leaves, and,after submitting them to chemical treatment,he extracted from them a white crystallinesubstance which he called cocaine. Nowthis substance, cocaine, was found to have thevery remarkable effect of paralysing the nerve -endings in any region of the body to whichit might be applied. It was found to beexceptionally poisonous but, when taken insmall amounts, it was shown to be capableof producing a remarkably exhilarating effectupon the human system, mental and physicalalike.

With cocaine came the conception of whatwe now term a " local anaesthetic." Cocaine,R was found, could be applied to any part ofthe skin for the purpose of rendering thatarea completely insensitive to pain. It couldalso be injected into the bodily tissues inorder to render the immediately surroundingarea painless.

Despite its highly toxic or poisonous nature,the value of cocaine for minor operations,such as teeth extraction and the superficialcutting of body tissues was at once recog-nised. The new drug was made the subjectof intensive chemical study. If it werepossible to find' out how the molecule ofcocaine was built up by Nature, it might thenbe possible not only to manufacture cocaineartificially but, better still, to improve onNature's drug and to formulate and build upmore powerful and, perhaps, less toxic localantcsthetics.

Composition of CocaineAt last, after much research work had

been done on the problem, the composition ofcocaine was finally elucidated. Natural cocaine

was found 'to have the followingchemical formula :HC-CH-CH. CH.CO. OCH,*

INCILH. 0. C000H5I

H2C-CH-CH,The chemically minded reader

will be familiar with the inter-pretatiem of chemical formula:similar to the above, complicatedthough they may be. The aboveformula represents a sort of atomicpattern made up of carbon,hydrogen, nitrogen and oxygenatoms. Careful study elucidatedthe fact that the anxsthetic actionof cocaine in some strange waywas connected with the CHgroup of atoms, which is markedwith an asterisk in the , foregoingformula. If this group of atomswere replaced by a hydrogen atomonly, then the whole of theanxsthetic and physiological actionof cocain.s: vanished completely.



Much research has shown that Nature has,in cocaine; built up a needlessly complicatedcompound to obtain anesthetic action.Decades of chemical work have demonstratedthe fact that it is possible to get anaestheticaction which is even more powerful than thatof cocaine by creating chemical substances ofmuch simpler composition.

In a way, modern chemistry has almostreduced the building -up of local:anestheticmaterials to a plain set of rules.

Arrangement of AtomsThere seems to be a certain arrangement

of atoms which, in some strange and as yetcompletely unknown way, produces anxstheticaction. For example, if the reader were tobuild up a new chemical compound havingthe following skeleton pattern :

R R N-C-C-O-C 0 Rhe would produce a chemical substancehaving a very pronounced anaesthetic action.

In the "aboveskeleton forinula, " R " standsfor certain groups of carbon and hydrogenatoms, such as : CH;;, C2113, C6115 and soforth.

It is along nowadays well -recognisedlines such as the above; that the various". cocaine -substitutes," as, for .4 instance,novocaine, alypine, stovaine, the spinal anxs-thetic, 'and numerous others . have beenproduced. Nowadays, cocaine proper is butlittle used in ordinary -medical and dentalpractice. Its place is taken by the manysynthetic drugs which have been broughtinto being as a result of its close investigationand study. Such drugs are, unlike cocaine,for the most part non_ habit-forming, andthey are much safer in action.

. The various disinfectants and antiseptics,whose names are nowadays legion, are, for

. the greater part, examples of the work ofsynthetic chemistry. These are essentiallydrugs which are toxic to bacteria and to alllowly forms of life. Although alcohol is apowerful antiseptic, it, unfortunately, injuresthe living tissues of the body. Hence itcannot be employed for this purpose.

Carbolic acid, a product of coal tar, was ourfirst general disinfectant. It can readily beproduced artificially from benzene or aniline,but it occurs abundantly in coal tar. Henceit is invariably obtained from that sourcealong with cresol and similar disinfectantsubstances.

Carbolic acid and the cresols have an irri-tating action upon living tissues. Indeed,they are extremely detrimental to the latter.For this reason, the various " fine " disin-fectants and antiseptics have one by one comeinto being. The majority of them are madesynthetically from coal -tar products. Manyof them contain chloride of iodine as essentialconstituents.

In this matter of disinfectant and antisepticproduction chemical research is still pro-ceeding. The ideal antiseptic, deadly togerm life but completely harmless to bodilytissues, has not yet been brought into being.Some of the bacteria which underlie variousinfections are highly virulent and resistant toexternal chemical influence.

AcriflavineA notable triumph in this line of research

was the introduction of acriflavine, a yellow -green fluorescent dye. Some of the mostcomplicated wound infections of the last warWere successfully fought with acriflavine andsimilar dyes, and there must still be livingmany veterans of the last period of hostilitieswho, if they but knew, owe their presentexistence to the properties of acriflavine andits relked synthetic compounds.

The next group of drugs which chemicalscience during the oast 50 years has concen-trated upon is that to which the term " fsver-reducing " may be applied. Quinine is thebest known of these. But quinine is a naturalcompound, and, as we have already learned,

it has resisted- all efforts to produce itsynthetically.

Acetanilide, C,H, .NH.CO.CH.;, a whitecrystalline material, formed by the action ofacetic anhydride on aniline, was one of theearliest antipyretic drugs to be producedartificially. For some years it had a vogue,but it was found to be irritant to the stomachand somewhat toxic in the bargain.

In 1888 the drug " phenacetin " was firstmade by von Bayer, the German dye chemist,in the Elberfeld laboratories of FriedrichBayer and Company. Phenacetin proveditself to be an extremely useful drug and its

Making synthetic drugs on .a large scale.phenacetin plant in operation.

large-scale commercialquickly effected.

In the following year "antipyrine " wassynthesised. It was less successful thanphenacetin, as was also the compound ofantipyrine with salicylic acid known assahpyrine. -

Enter AspirinThe properties Of oil of wintergreen in

treating rheumatism have long been known.

manufacture was

Wintergreen oil contains salicylic acid,which, in the form of its salts, is also ofextreme value in rheumatic treatments.Salicylic acid itself cannot be used for anysuch treatments because the free acid is fartoo irritant to the stomach and intestines.It was discovered, however, that just as aceticanhydride and aniline could be reacted to-gether to form a useful antipyretic drug,aceranilide, so, too, could acetic anbydrideand the very potent and medically valuablesalicylic acid be combined to produce a whitecrystalline material which was called acetyl-salicylic acid. Subsequently, when theextreme value of acetyl -salicylic acid as anantipyretic agent and as a headache and nerve -pain killer became recognised, the productwas manufactured under the now universallyknown name of " Aspirin."

Aspirin was a complete German monopolyprevious to the last war, but since that timeit has been continuously produced in England.Constituting, perhaps, the most popular of allcommon drugs, aspirin is purely of syntheticorigin. It is safe in use because its physio-logical action is mild and steady.

Another group of drugs which have beenmuch studied by modern chemistry are the" hypnotic" or the sleep -producing drugs.Bromide of potassium,taken in large quantities,can produce sleep, but in normal smallamounts it acts merely as a sedative or a .

nerve-quietener. The first of the sleet:ILproducers to be made synthetically, waschloral hydrate, which was introduced to ..medical practice in 1869. This material ismade by the action of chlorine gas on alcohol.Its success led to the search for other syntheticchemical drugs of a like nature. Eventuallya more powerful drug, sulphonal, was firstproduced at Barmen, in Germany, and aftersulphonal came various other sleep -producingagents.

An Evil -smelling MaterialThe parent substance of sulphonal is

mercaptan, an incredibly evil -smellingmaterial, of which little as ',:too,ocoth of amilligram is offensive to the nostrils. In viewof this fact, when the sulphonal factory atBarmen commenced operations the worthyinhabitants of the district rose up in armsand threatened to take the direst of pro-ceedings against the new factory unlessdie terrible and over -powering smell ofcats " was immediately suppressed.

The sulphonal factory had tomove its site several times beforeeventually it discovered a techniqueof masking the odour of m5rcaptan.Nowadays sulphonal is made invarious parts of the world.

The most powerful of themodern sleep -producing drugs arebased upon the compound knownas barbituric acid. These wereintroduced during the openingyears of the present century.

The field of chemical drugs is avast one. Year after year new drugsare brought out and tried. Someof them prove Wanting. Othersmanage to supplant existing drugs

The origin of many present-day druv. coal -tar still of a modern type.


66

PHOTOGRAPHY

NEWNES PRACTICAL MECHANICS November, 1942

Photo TintinHow to Prepare the Prints and Apply the Colours

By JOHN J. CURTIS, A.R.P S

TINTING of photographs has been apopular sideline with many amateursfor several years, but never has it been

such a favourite pastime as during the lasttwo winters.

While the work does not call for specialskill, yet it is surprising what excellent resultsare being obtained by those who have per-severed with it and gained some experience;they have apparently acquired the knowledge,so necessary in all colour work, of being ableby mixing to get just the right tint and thecorrect balance of colour into the picture. Theactual design or base for colouring is alreadymade for us in the photograph and this, asyou will recognise, Is the most skilful part ofan artist's work. All we have to do is to applythe colours.

There is, therefore, no reason why everyamateur should not try this extra branch ofhis or her hobby, and I would recommend thesets of tints as put out by Johnsons. Theycomprise nine of the most useful colours invery concentrated liquid form, each in asmall bottle and the whole nine racked in anupright, position in a box so that they neednot be removed from the box when in use.Each tint is capable of considerable dilutionto enable thin washes to be used when onlya suggestion of colour is desired, and each istransparent so that when it is placed on theimage of the print the image is visible, butin colour.

Beginners' MistakesMost beginners at first make the mistake

of using the tints too strong ; it is very seldomthat deep colour is required except forflowers or very small items appearing in theprint, and then it is applied by means of afine brush allowing only pin points of colour.Usually it is better to use a dilute strength,blot this off with clean blotting paper, andgive a second, third or a fourth applicatiortif necessary until the desired depth of colouris reached.

Do not attempt to tint on a dry print, itmust be soaked in clean water first and thesurplus water blotted off. This soaking willsoften the gelatine of the emulsion so thatit will take the colour ; with some of thepapers to -day the emulsion is so hardened inthe m'iking as to necessitate soaking them forseveral minutes in hot water cold seems tohave little or no effect. If the prints are oldthey will require prolonged soaking, and ifthey are " greasy," due to handling, it is aswell to rub them with a wad of cotton woolsoaked in methylated spirits.

There is no- doubt that a print that hasbeen sepia toned previously will give a muchmore pleasing and artistic result. Details ofsepia toning were given in PRACTICALMECHANICS for March, 1942, in which youwill find the process and formula; fully de-scribed. I do not favour a high -glossysurface; matt surface is, in my opinion, muchthe better.

Brushes are hard to get at present, but try topurchase two or three good ones, it pays tohave fine quality. The thin or fine grades, asNos. o, I and 2 will be found to be the mostuseful. I believe the present prices areround about Is. 6d. to is. 9d. each, but withcare they last a long time. The current pricesof the sets of tints are 3s. 6d. for small andgs. 6d. for the large sets which contain, besidesthe nine bottles of tints, tubes of tinsel andmedium, also two saucers for mixing the dyes.

The colours included in the sets are asfollows : blue, brown, crimson, flesh, green,orange, scarlet, violet and yellow, and it mustbe remembered that each is intermixable sothat a very extensive range of tints in heavyor pale tones is obtainable.Mixing. Colours

Mixing of colours to obtain certain effectsis, as everyone knows, part of the artist'straining, and to one whose profession is,painting it is undoubtedly very valuableknowledge, but we amateurs must be satisfiedwith knowing the elementary rules and tomake our own tests as and when we requireparticular effects.

RussetWA

pp

set

--Diagram of a colour wheel, showing therelationship of the primary, secondary, and

tertiary colours.The accompanying diagram is taken from

the 1934 copy of " The Print User's YearBook," to the publishers of which I tendermy grateful acknowledgments, as I havefound it of very great use. On the colour -wheelwill be found the three primary colours-red, blue and yellow-represented as R., Band Y; then the three secondaries-orange,green and purple ; and the three tertiaries-olive, citron and russet brown. On the wheelwill also be found the " three-quarter "shades falling between the primaries and thesecondaries.

It is necessary to know how to break downcompound colours to their constituent primar-ies ; for instance, each secondary is made upof two primaries, as O -=R LY, and thetertiaries are made of equal parts of twosecondaries, as russet =0 +P. If you proceedto break down the tertiaries to the primariesvia the secondaries you will get russet equals0 +P =R+Y d -B, which simplified isRRYB, which means that this tertiarycontains two parts of its "related " primary, red,and one part each of the other two. In thewheel the tertiary always lies beyond its" related " primary.. The three-quarter shadesare held to contain two parts of one primaryand one of another.

A Colour ChartThis method should prove quite usefid in

helping you to arrive at many combinations ofcolours, and for those who desire a chartshowing the actual result obtained by super-imposing one colour over another I wouldsuggest the following as being the easiest andmost effective. Rule a sheet of paper in squaresas a " graph "- having nine squares from leftto right and nine from top to bottom, equalling8t squares in all. Over the top of the firsttine from left to right write the names of the

tints in your set, commencing with blue andfinishing with yellow. Now repeat thesenames in the same' order alongside the firstdowner and column of squares on the left side.Your first square has the word " blue '1 -over it -

and on the side. Take a brushful of the bluetint and fill up the first column of squares onthe left from top to bottom; the second shouldthen be filled with brown, the third columnwith crimson; the fourth flesh, and so on untilthe whole of the upright columns are colouredwith" the tint mentioned at the top of each.Having washed the brushes, proceed to get theeffect of superimposing by covering half ofeach square on the top line from left to right

.with blue. Do this diagonally across thesquare; the second row down will be treatedwith a superimposing of brown, the third withcrimson, and so on, until the whole of thechart shows two colourings in each square.This will show at a glance what you mustexpect when using a mixture of two of thedyes in their concentrated form. A fewexperiments made in conjunction with thesetwo charts will put you on the right way formixing in order to get a special tint, but youmust beat in mind that it is better to workwith weak colours and build up the depth byseveral applications rather than taking a shortcut and Using the strong concentrated liquid.Prints with heavy trees and foreground ofgrass plots call for a fair amount of work toget the effect of greens and browns in bothtrees and grass ; but where you have a printof an old country whitewashed cottage in agarden, showing a few flowers in bloom, donot attempt to put any tint on the cottage,but add your spots of colour to the flowers andto the creeper on part of the walls. Rememberalways, too much colour may spoil your effort,whereas too little can always be added to.Colouring

It may happen that sometimes you haveused too much or too deep a colour, and mustremove some of it. Wash the brush and fill itwith clean water and go over the part you want" removed," then blot off after a few seconds ;repeat this until you have got what you want.Should you desire to remove all the colouringand to start afresh, then allow the print toremain in soak, as this will clear it of mostof the colour. The colours are made fromaniline dyes, and you are dealing with agelatine surface on the paper, and in thisgelatine are quite a number of chemicals.The colours are fairly " fast," and will standup to light for quite a long time, but they arenot permanent; therefore, if your print ismounted and framed it should not be hungwhere the sunlight can reach it for manyhours during the day. -

Those who have made some lantern slideswill do well to tint some of them with thesecolours, as, being transparent, they can beused with very good effect, and make a splendidrelief to the black and white when put throughthe lantern. More care and skill is requiredwith the tinting of slides to allow for themagnification of the image which occurs whenthe slide is shown on the screen, but a littlepractice will soon put this right.

When preparing a dilute solution for washwork, as for skies and sea, one or two dropsof the colour with about 3o drops of waterwill be found to be about the correct strengthwith which to work. Quick application of theblotting -paper after each wash of the tint isadvisable, as it helps to get the colour moreuniform and free from brush trucks



THE WORLD OF MODELS

Ready to get under -way. This fine model drifter and its builder, Mr. S. Tilley.

SOME enthusiasts start the model hobbyin war -time because of the " Stay atHome " recreation campaign. Others,

who were keen before the war, try to continuetheir hobby under great stress and often turnit to the war effort.

For some time I have known Mr. S. Tilley,and he is one of those model hobbyists ofmany years standing, who is still carrying onwith his model -making during the war. Inbusiness he is a very busy lorry proprietorand after his long runs across country onGovernment transport, he finds relaxation inhis old pastime of building models. He hasbeen at work for the past four years or soon a model of a Yarmouth drifter, and recentlyfinished this fine super -detail working scalemodel.

In September of this year he gave ademonstration of the drifter on a lake in apublic park at Northampton, and the interest-ed crowd of onlookers included a contingent ofthe local Sea Cadet Corps, whose presencelent a truly nautical air to the display.

Mr. Tilley, the maker of the model drifter,is One of the civilian instructors at Northamp-ton branch of the Sea Cadet Corps, and therecent demonstration was primarily for thosedirectly in the Sea Cadet movement, but, asone would expect, members of the generalpublic were also there in force !

The model,which is steam driven, was builtfrom drawings of the prototype supplied byMessrs. Crabtree, of Great Yarmouth, whoare well-known builders on the East Coast ofthis type of fishing vessel.

In peace -time the steam drifter, lowering avertical net over the bow and drifting to itwith foremast lowered, was used entirely forfishing. It is fitted with a powerful capstanin place of the trawl winch, has a compoundengine, and could parry 5o tons of fish.To -day, however, practically every dfifter hasbeen taken over by the Navy and isused for minesweeping, submarine spotting,patrolling and other auxiliary duties ofa similar nature.

Details of the ModelIt is 6 ft. long with a gin. beam and is

.to a scale of jin. to the foot. Mr. Tilleystarted-as an experienced model -makergenerally does-on making the engine andboiler first. After a careful study he decidedon the Stuart Compound Launch engine withreversing motion as the best type for the job.This has cast-iron cylinders of lin. and 'lin.bore with in. stroke, weighs approximately

41b. and is a very economical engine in steamconsumption.

He built the engine from castings pur-chased from Messrs. Stuart Turner and madean excellent job of it, despite the fact that inhis workshop he only has a Sin. lathe, a smalldrilling machine and a few bench tools. Theboiler feed pump he also constructed from aset of Stuart castings.

The boiler is made of copper and is rivetedand not brazed. It is coal fired and has thespecial featnre of a water-sooled clOor. Alsoit is fitted with a super heater. The engineand feed pump are fed by automatic lubri-cators.

When he had completed the steam planthe ran the bench tests, which were mostsuccessful, in his workshop, and the plant whenin service will maintain the boat in runningtrim 0 -three-quarters of aft hour withoutattention.

Now as to the hull of the drifter, this iscomplete with timbers, forekneei, apronsand dead woods, and is carvel built. Theplanks are of teak and the lailWarki'are builtin the style of the prototype, in teak, oakand ash.

Mr. Tilley's method of construction was bylaying the keel and then fixing all the timberS,which We in larger boats would call the" ribs." He then did the planking and madesuch a good job of this that no caulking at all

By "MOTILUS"Model of a Steam Drifter and a

Gauge "0" Model Railway Layout

was needed, and the hull was simply finishedoff with a coat of paint to colour it. Hecarved the name in box wood and finishedit off in leaf gold, exactly as on the prototype.

Deck PlankingThere is too feet of planking on the deck,

and the pitching in between the planking is putin with black ebony wood. Also at least75ft. of half round brass of various dimen-sions from 3/,12in. up to 3/,bin. is used onthe model.

It is driven by a four -bladed propeller, andthe thrust is taken by ball race and properpacking gland. The blocks and pulleys aremetal centred and wood sheaved.

The fairleads, bollards and riding lampsare all carved out of the solid and are notcastings, which model makers of experiencewill realise was no small task. The venti-lators are made out of the sheet and riveted,and the funnel is also plated and riveted.All the 1J bolts and shackles are built up andsilver soldered. The wheel house is made ofsheet brass, riveted with angle irons, etc.,and includes the usual fittings inside. Thewheel was made out of an old croquet malletand a t ft. boxwood rule. It is properlyfelloed and banded with half -round brass.The steering wheel is geared down to ten toone with the steering chains.

Besides being a keen and expert modelmaker Mr. Tilley takes a great interest in allgood craftsmanship, anything from periodfurniture to an old watch, and on hiS travelshe is often able to secure many examples ofthe work he admires. His home containsquite a number of beautiful antiques.

Gauge " 0 " ModelsMr. C. B. Smith, of Lincoln, whose railway

has often featured in these pages, has recentlysent me a prcture of five of his gauge " 0 "models outside Bincliff Station on what heCalls the " Bincliff, Lakeside and Shedley "branch of his L.M.S. layout. When he has,ballaSted his track there will be a further" note of realism " to mention about hisline !

An impressive team of locos on part of Mr. Smith's "0" gauge railway

-



Our Busy InventorsBarrage StreamersTHE barrage balloon lias its limitations. It

cannot soar very far towards thestratosphere. Since many enemy 'planes flyat an exceedingly lofty altitude, the barrageof the balloons stops short of the high -flyinghostile aircraft. Admittedly it prevents themfrom coming inconveniently low.

An improved device for intercepting aircraftis the subject of an application which has beenaccepted by the British Patent Office. Thenew invention contemplates the use ofstreamers which can be flown at heights farabove the balloons. The aim of these streamersis to become entangled in the airscrews ofthe raiding aircraft.

The device consists of streamers of pliablematerial filled with hydrogen or other lightgas, and arranged to be flown from a suitableanchorage at a height considerably in excessof that attainable by a barrage balloon.

Strong and light, the streamers will requireonly a wire or other means of attachment.Silk has been suggested for this purpose.

Should a raider pass near such a streamer,the air flow will tend to suck the streamerinto the airscrew, with almost certain disas-trous results to an enemy 'plane.

To Warm the PilotTT goes without saying that in-

tense cold is a very greatdrawback to the pilot and othermembers of an aeroplane crew.it is true that thick clothingprovides protection against frost,but its bulkiness is apt to inter-fere with the wearer's freedomof movement.

To obviate these drawbacks,an inventor has submitted to theBritish Patent Office an idea forimproved electrically heated wear-ing apparel. This clothing is ofvarious types, such as outer gar-ments, shirts, socks, gloves andshoes.

Associated with these articlesof wear is thin, flexible sheetmaterial forming lightweight elec-tric heating units permanently orremovably secured to the portionsof such garments it is desired toheat. And this is effected without appreci-ably increasing the weight or thickness. Atthe same time, the garment is not causedto be stiff, bulky and uncomfortable.

To take an example of clothing heatedaccording to this system, an under -garmentmay be of union suit type. Secured to theouter surface of this suit are any desirednumber of electrically -heated units. Theseunits are mounted in a protecting bag orpocket detachably fastened to the suit bybuttons, snap fasteners or other means forremovably attaching the bag to any positionon the suit.

Portable Spraying OutfitAN application for a patent in this country

relates to a portable spraying outfit.The device is a small tank which is speciallyadvantageous in connection with fire -defence,as it can be immediately picked up, put on,carried and operated by one person.

This tank has a pair of shoulder straps ofhook -like form, thus enabling it to be morerapidly placed on the back than is the casewith the harness type which has preceded it.

Detachably connected is a flexible tubeleading to a hand pipe, or syringe, the barrel

By "Dynamo"of which is ordinarily supported in a springclip on one of the shoulder straps. The pumphas an extension lance and a spray nozzleresembling those in stirrup pumps.

The tank is rectangular in shape, some-what narrow from back to front, so that theperson carrying the outfit can pass throughtrapdoors and other restricted openings.

The whole assembly is carried on the user s

The information on this page is speciallysupplied to " Practical Mechanics " byMessrs. Hughes & Young, Patent Agents, of7, Stone Buildings, Lincoln's Inn, London,W.C.2, who will be pleased to send free toreaders mentioning this paper a copy of theirhandbook, " How to Patent an Invention."

shoulders, leaving both hands free for climbingladders or manipulating sandbags.

It is possible at once to sever the pump andhose from the tank, so that, when it is empty,they can be fitted to a spare one. In fact,any number of tanks may be stored full ofwater or fire -extinguishing liquid ready forimmediate use.

This device, invented by an American, is for picking up incendiarybombs and trapping them in a metal container.

For Fire-fightersA FACE -SHIELD of heat -resisting material

with a transparent panel may be fixedto the tank. Normally the shield is held byclips flat against the back of the tank ; butit can be instantly detached by a downwardpull. And a clip then serves to secure theshield on to the pump barrel.

This shield should prove an effectivedefence against the enigmatical incendiarybomb. New ideas are being used by the enemyin connection with this bomb, so that onedoes not know how it is going to behave.

The usefulness of this portable tank is notlimited to fire -defence ; the appliance isequally suitable for horticultural or industrialspraying.

Second FrontMEN'S ties have a habit of wearing out

principally at one point-the frontportion. To deal with this drawback aninventor has contrived a tie in which thefront portion can be detached and replacedby new material.

According to this invention, the new fronttie portion is tapered at its inner end, which

may be inserted and secured within the openend of a tie from which a correspondingportion has been removed.

Preferably the front portion is stiffened orstrengthened along its inner end. Fasteningtags are provided, by means of which theinner end may be inserted into the end of theremaining portion and made secure. Clipsmay be passed through the fabric of the oldtie and bent over its outer surface. However,instead of clips, the inner end of the new frontcan be stitched in place in the open end of anexisting tie from which the old front portionhas been removed.

Pencil for LightingFOR igniting the burners of gas stoves an

improved striker device has recentlyappeared. This comprises a flint and a handholder. The holder is in the form of a pencil -like casing of wood, and contains a flint of theigniting composition usually found in cigarettelighters.

The material of the holder is of such a kindthat it will wear away with the flint, as thelatter becomes worn down during use. As aconsequence, the outer face of the flint isalways capable of rubbing contact with the

abrasive surface. However, ifmade of wood the holder maybe sharpened from time to timeto expose the resulting outerextremity of the flint in the waythat a lead pencil is sharpened.

To prevent the loss or mis-laying of this lighter there is anarrangement whereby it can beattached to the gas stove.

A Sound PropositionMUCH thought has, doubtless,

been expended in an en-deavour to contrive a soundproofwall.

An inventor has applied for apatent in this country for ameans of furnishing-to quotefrom his specification-" a soundbarrier or insulating partitionwhich will absorb a large part ofthe energy of the sound wavesimpinging upon its surfaces withresulting minimum transmission

and reflection of the sound."His idea is a sound barrier wall or door so

constructed that it has an air -imperviousdiaphragm. On each side of this diaphragmis a layer of intersticed material.

In the minds of many people the preventionof noise is a problem which should be tackledwith vigour. Over and over again, for example,we are enjoined by the B.B.C., in the interestof night workers who sleep during the day, tomodify the tone of our wireless sets.

But something may be said in favour oftraining oneself not to be hypersensitive tonoise.

TWO NEW VEST-POCKET BOOKS !

WIRE AND WIRE GAUGESBy F. J. CAMM 3/6 or by post 3/9

NEWNES ENGINEER'SPOCKET BOOK

By F. J. CAMM 7/6 or by post 8/ -

Obtainable from all booksellers, or by postfrom George Newnes, Ltd. (Book Dept.),Tower House, Southampton Street, London,

W.C.2


I

),p

November, 1942 NEWNES PRACTICAL MECHANICS 69 -

.7: QUERIES0,4tl'A ENQUIRIES

Making an Induction CoilWILL you please advise me regarding

the construction of an inductioncoil with an output of about 40,000 to5o,000 volts, working from a standardcar battery. I have sufficient facilities toconstruct a coil -winding apparatus. Canyou give me full details including thefollowing points :

x. Gauge and type of wire for primaryand secondary.

2. Number of turns for primary andsecondary.

3. Construction and material for core.4. Does the speed of interruption

affect the output, and would it be anyadvantage to mechanically control it ?

5. What determines the general shape ?For example, it could be wound, say,24in. diameter by sin. wide, or 36in.long by Sin. diameter. I quote extremecases so as to make my question clear.

6. Is it possible to draw off varyingvoltages by making contacts at differentradial positions ?

7. Should such a coil 'be cooled ?8. Where can suitable wire be pur-

chased ?-E. R. Bailey (New Milton).

AN induction coil to give an output of40,000 to 50,000 volts at ordinary

atmospheric pressure and conditions wouldcorrespond to a tin. spark, for which thefollowing data would be appropriate :

Iron Core. Built up of 22g. soft iron wire7Nn. long by Nn. diameter fitted with ebonitebobbin 6!,in. overall length by 3M. diameterwith fin. thick cheeks.

Core insulation. 3 layers of 15 -mil empirecloth wrapped tightly round the .core.

Primary. 2 layers of No. 16 S.W.G. d.s.c.copper wire. This suits a 6 -volt battery.If required for 12 volts wind with three layersof No. 18 ditto.

Primary insulation. 6 layers of 15 -milempire cloth, close wrapped and overwoundwith a layer of fine thread.

Secondary. tilb. No. 38 S.W.G. d.s.c,copper, wound preferably in four flat sections,separately wrapped with silk empire cloth,and assembled side by side on the core, thejunctions being made afterwards.

Condenser. 4o sheets of tinfoil, 6in. by 4in.,with thin waxed paper between, bound tightlytogether between glass plates and soaked inmelted paraffin wax.

A motor -driven mercury -type contactbreaker gives better results than the ordinaryvibrating hammer -head interrupter, and thesecondary output can be varied to a certainextent by varying the speed. Coarse regulationis also obtained by a variable resistance inseries with the primary winding, consisting ofabout to ohms of 2 amperes carrying capacity.Replying to further points, extremely shortcoils are very inefficient, owing to the increasedmagnetic leakage between the poles. Thereis no necessity whatever for artificial coolingof the induction coil. To obtain instrumentwires is a difficult problem at the momentunless Government Contract Nos. can begiven with the order. Try Messrs. Ward &Goldstone, Ltd., Frederick Road, Pendleton,Man ehester

A stamped addressed envelope, three pennystamps, and the query coupon from the currentissue, which appears on back cover must be enclosedwith every letter containing- a query. Everyquery and drawing which is sen: must bear thename and address of the reader. Send yourqueries to the Editor, PRACTICAL MECHANICS,Geo. Newnes, Ltd., Tower House, Southampton

Street, Strand, London, W.C.2.

Electric Soldering IronI. RECENTLY purchased two electric

soldering irons rated at x to/x2o volts,40 watts. Our mains supply is 200 voltsA.G. I have been told that I cannot usethem in scries, or with a resistance incircuit because of the A.G. supply. Is thisso ? Can you supply me with the detailsof a transformer giving at least t ampereon the secondary with tappings at too and

200V Line A

2 -Pin Plug(4 Socket

Method of reducing sup-ply voltage to suit lowwattage soldering iron.

100VSolderingiron

x to volts, and the primary tapped at zoo,210, and 23o volts ? Could such a trans-former be used as an auto -transformerworking on no volt. (A.C.) supply?-J. M. Firth (Beckenham).THERE is no necessity to employ a relatively

expensive step-down voltage trans-former in order to utilise your to -voltsoldering iron on a Zoo -volt A.C. circuit.As the consumption in watts is so low, andthe iron probably in occasional use only, thesimplest arrangement is to obtain a potentio-meter -connected resistance of 200 ohms

0.5 ampere carrying capacity, and connect itwith your soldering iron as shown in. theaccompanying diagram. The voltage betweenpoints B and C in the diagram will varyaccording to the position of the slidingcontact C, so that if the latter is adjusted toabout the middle point of the resistanceA B there will be a terminal voltage of toovolts at the soldering iron connections, andthe heat of the iron can be graduated nicelyby sliding contact C towards one end or theother to raise or lower the terminal volts atthe iron.

THE P.M. LIST

Salt Bath Electric FurnaceWILL you kindly explain the principles

of high temperature electricfurnaces as sometimes used in themanufacture of pottery ? What is thematerial used for the elements ? Iunderstand there is a new high tempera-ture electric furnace called the SaltBath; would you also explain the principleof the heating element employed ?-Samuel Adams (Cookstown, N. Ireland).THE Salt Bath is one in which the salt,

consisting principally of bariumchloride, is heated by the direct passage ofcurrent through it between immersed elec-trodes. There are no " elements."

There are several types of electric furnacesused in the pottery industry, e.g., tunneltype kilns for firing, box type furnaces forfiring, etc. It would take up considerablespace to describe these in detail, and wesuggest you write to the General Electric Co.,Ltd., Witton, Birmingham, or BirminghamElectric Furnaces, Tyburn Road, Erdington,Birmingham, for information, stating the kindof heating operation in which you are in-terested, the material you wish to heat, theweight of each piece, the weight of the totalfurnace load (including boxes or containers,if any), size of pieces, dimensions andweight of containers, working temperature,particulars of electric supply available, timeallowed for bringing the charge to tempera-ture and holding at temperature, if necessary.

Seasoning of TimberT HAVE been given to understand thatA there is now a process which enableswood to be seasoned in a period of weeks.This result I am assured is obtained bythe use of steam and air blasts. I shallbe glad of any information on thissubject.-H. Spencer (Preston).FOR quite a number of years, timber has

been artificially seasoned by means ofspecial " kiln " treatment. Such treatmentvaries considerabfy, but, in principle, itconsists in packing the timber in horizontaliron kilns which are brought to a definitetemperature by means of steam heating. Theinterior humidity of the kilns is also controlledby means of steam injection. Several ofthese kilns are usually in the possession ofevery large timber company. The kilns arenot only valuable in the respect of seasoningtimber artificially, but they also serve a doublepurpose in eradicating destructive wood -beetlepests (such as " Powder -Post " beetle) whichmay lurk unsuspected in the interior of thewood.

The undermentioned books may appeal toyou in ' the above connection, and, mostprobably, you could obtain them eitherthrough the County 'Library, Preston, orthrough the Harris Institute, Preston :

" Seasoning and Preservation of Timber."By E. G. Blake.

(Continued on page 16, Cyclist Section.)

OF BLUEPRINTSThe P.M. "PETREL " MODEL

MONOPLANEComplete set, 5s.

The I-c.c. TWO-STROKE PETROL ENGINEComplete set, Ss.

STREAMLINED WAKEFIELDMONOPLANE -2s.

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P.M. TRAILER CARAVANComplete set, 10s. 6d.

The above blueprints are obtainable, post free,SUPER -DURATION BIPLANE from Messrs. G. Newnes, Ltd., Tower House,

Fuli-size blueprint, Is. Strand, W.C.2.

The " PRACTICAL MECHANICS "S20 CAR(Designed by F. J. CAMM),

10s. 6d. per set of four sheets.

"PRACTICAL MECHANICS" MASTERBATTERY CLOCK

Blueprints (2 sheets), 2s.

The " PRACTICAL MECHANICS " OUTSPEEDBOAT

7s. 6d. per set of three sheets.

A MODEL AUTOGIROFu!! -size blueprint, Is.



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Also architecturalmodels and fittingsand parts for modelmakers. War -timeStock List (LI12)of model suppliesstill available. 6d.

post free.Bassett-Lowke ModelBurrell Type Traction

Engine.

REALISM IN MINIATURE.

Bassett-Lowke" Flying Scots-man " Model No. 4472.

Model Engineers-amateurs and professionals-aremaking. a great contribution to the War effort ;and materials hitherto used for BASSETT-LOWKEmodel railways, model engines ',Ind model ships areto -day needed for more vital purposes. But whenpeace gives us the "all -clear" we shall be ready to"go to it " and resume production of those detailperfect scale models which for so many years havebeen a delight to the Model-makingWorld. And inplanning for post-war production we aim to maintainand even Improve upon the high standard of work-manship always associated with the name " BASSETT-LOWKE."

BASSETT-LOWKE LTD.,NORTHAMPTON

LONDON : MANCHESTER :112, High Holborn, W.C.I. 28, Corporation St.

BOOKS FROM OUR CATALOGUE

PANEL BEATING and SHEETMETAL WORKBy Sidney Pinder. 4s. net.

LATHE OPERATOR'S MANUALBy B. Richard Hilton, Grad. A.M.I.W. 6s. net.

BENCH WORK and FITTINGBy W. J. Peck, M.Eng., A.M.I.Mech.E., etc. 3s. 6d. net.

MACHINE SHOP PRACTICEBy W: C. Durney, A.M.I.Mech.E., A.M.I.A.E.

7s. 6d. net.

RADIO SIMPLIFIEDBy John Clarricoats. 4s. 6d. net.

Are you in doubt about the kind of book you thinkwill help you most ? You should get Pitman'sGuide to Technical Literature. It's entitled" Books aboui Jobs," and is arranged in sectionswhich deal with Aircraft Engineering, EngineeringDrawing, Ratefixing and Estimating, Foundry -work and Metallurgy, Mechanical Engineering,Electrical Engineering, Factory Management, Radioand Advanced Radio Theory and Practice.

PITMAN KINGSWAY, LONDON, W.C.239-41, PARKER STREET,

SIR ISAAC PITMAN & SONS, LTD.

HIGHSTONE UTILITIES. .

CRYSTAL SETS our latest Model is aREAL RADIO RECEIVER and is fitted with aPERMANENT CRYSTAL DETECTOR. WHY:NOT HAVE A BET IN YOUR OWN ROOM ORAs A STAND-BY 7-9/6. bog ed.PERMANENT DETECTORS, 2/6, poet 3.1.HEADPHONES, reconditioned. 8/8, 91, 10;8.

BELL TRANSFORMERSThese guaranteedtransformers woe!,from any A.C. Mainegiving 3, 5 or 8 volts

" output at 1 am p..operate bulb, buzzeror bell. Also providesan &RI'. light inbedroom. shelter. ete. PRIPI: 6 -. POST 5d.

MORSE KEYSPractise on a regulation size Tapping Key. Ourheavy brass model is mounted on a wooden base,has an adjustable gap and nickel contacts. Key isaired to work buzzer or flash lamp by using a 41 -voltbattery or the transformer illustrated above.BRASS KEY, 8/9, Chromium plated, 7/8. W.O.Mode] with heavy brass bar and the addition of afront bracket, SM. Chromium plated, 10/8. Theabove keys are supplied to the Services for Morseinstruction. Slightly. smaller Key, 5/-. Junior Key,mounted on a bakellte base together with a buzzer,6/... Should you require a complete outfit, our D.X.2Set consists of a heavy key mounted on a largepolished board, Dims 71in., together with a buzzer,flash lamp bulb and holder with two switches tobring either into circuit. Terminals are also pro-vided for distant sending and receiving. 19/8, post 84

MICROPHONESJust the thing for impromptuconcerts, room to room com-munication, etc. Bakelitetablemodel 8/9, Suspension type asIllustrated 8/8. Post 611.

Pitting instructions included.

BUZZERS. No. 9.Square single coil model 216.

,,4 No. 3 HEAVY DUTY, double..,41,11.- coil, 9/9. post 14.

GENERATORS, triple magnet P.O. type,can either be turned by hand (handle not supplied)or valley fitted and power driven. Gives 70-80volts, 25 ma. A.C. can be used for ringing bells,lighting bulbs, or us a shocking coil. 8/13, poet 13d.

SOLDERING IRONS, Adjustable Bit, 200/210 T.,9/6, post es. STRONG MAGNET8,9d. each, post 5d.SEND ld. 8. A. E. FOR LIST B.P. OF USEFULELECTRICAL ACCESSORIES. Money refunded IInet completely satisfied. Letters only. Please

include postage, any excess will be refunded.

HIGHSTONE UTILITIES58 New Wanstead, LONDON, E.11

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NAME

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P.M.9I

WANTEDGood qualitysecond - hand

models of

LOCOMOTIVESCOACHESTRUCKS

STEAM BOATSSTEAM ENGINES

Must ba ingood working

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Also

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GALPINS-4LECTRICAL STORES -

21, WILLIAM ST.,SLOUGH, BUCKS.'Phone: SLOUGH 20855TERMS : Cash with order

SHEET EBONITE, size 12in. by llin. byI /32in.'',c4 quality. Price 4/- per doz.,post free.ELECTRIC LIGHT CHECK METERS,well-known makers, first-class condition,electrically guaranteed, for A.C. mains200/250 volts 50 cy. 1 phase 5 amp. load10/- each ; 10 amp. load, 12/6, carriage 1/..AUTO TRANSFORMER, 1,500 wattslappings,,0-110.200-220 and 240 volts forstep-up or step-down. Price 25, carriagepaid.ROTARY CONVERTOR, D.C. to. D.C. ;input 220 volts D.C. ; output 12 volts at50 amps. D.C., ball bearing, condition asnew. Price 210, carriage forward, or 17/6passenger train.ALTERNATOR, output 220 volts, 1 ph.,50 cycles at 180 watts, will give 1 amp.easily, speed 3,000 r.p.m. ; self -exciting.condition as new. Price 44,, carriageforward, or 15/- passenger train.TRANSFORMER, input 230 volts, 50cycles, 1 ph. ; output 1,100-0-1,100 voltsat 220 milliamps, and 6 volts C.T. threetimes, earth screen, wound to BAR.,weight 32 lbs. Price 26, carriage passengertrain 7/6.MOVING COIL METERS, high grade, tin.dia., flush mounting, reading 0-50 milli -amps. 50/- post free.110 V. D.C. KLAXON MOTORS, precisionmade, ball bearing, variable speed,approx. 1/10th h.p., laminated fields, asnew. Price 30/- each, post free.MOTOR BLOWER, 110 volts, D.C., 61n.dia. inlet and outlet, 1-11.p. motor, condi-tion as new, portable lightweight, 1,800r.p.m. Price 27, carriage paid.SEARCH OR FLOODLIGHT,.201n. dia., onswivel stand, Mangin mirror reflector,fitted G.E.S. lamp holder. Price 111/10/-,carriage forward.ROTARY CONVERTER, D.C. TO A.C., noname plate or particulars, estimated rating220 volts, D.C. input, 150 volts A.C.output al 1,000 watts, condition as new.Price 210, carriage forward.LOUD RINGING BELLS, working on 20volts D.C., Bin. dia. gong (hell metal),plated, waterproof, absolutely as new.Price 30/-, carriage 2/-.ROTARY CONVERTOR, D.C. to A.C.,input 35 v. at 16 amps. D.C., output 24volts, 100 cycles, speed 3,000 r.p.m.,4 pole, ball hearings, condition as new.Price S5, carriage paid.1_KW. TRANSFORMER, input 100 voltsat 100 cycles, single phase, output 10,500volts, centre tapped to earth. Price24/10/-, carriage forward.

X-RAY TRANSFORMER, output 45,000volts at 5 k.v.a. constant rating, 50 cycle,single phase, input tapped for 70, 105, 150;200, 220 and 240 volts, oil -filled tank.Price 130, carriage paid.D.C. MOTORS,. 110v. and 220v., approx.1/10 h.p., series wound, in perfect workingorder. Price 12/6 each, carriage 1/..Please state voltage required. .

HEAVY. DUTY CABLE, V.I.R., andbraided, in first-class condition, size 37/13,lengths 30 to 40 yards. Price by the length6/- per yard, carriage forward, or 8/- peryard for short lengths, carriage paid.200 AMP. SWITCH FUSE, three-way.Ironclad, unused, 400 volt, size overall30in. x 12in. x 121n., maker E.N. Bray,

11

.i Ltd. Price 26, carriage forward.THREE-PHASE TRANSFORMER, coresize, 211u. by 17in., each pole area 7. sq. in.,each pole double wound D.C.C. copperribbon, rating not marked, condition firstclass, weight approx. 2i cwt. Price 1110,

1 carriage forward.110V. D.C. MOTOR, compound wound,i h.p. 2,200 r.p.m., bah bearing, conditionas new. Price 23/15/-, carr. paid.

`t LIGHTWEIGHT HEADPHONES, 1201 ohms., complete with headbands, .cords11. and G.P.O. plug, in good working order

7/6 pair, post 6d.RADIO FREQUENCY ampmeter reading0-2 amps. ; full scale deflection 2 m/a,resistance of coil 2 ohms ; flush mounting,24 -in. dia. moving coil, maker " Elliott."Price 23/10/-, post freo.MOVING COIL meter, tin. dia., flushmounting, reading 0-50 nila., maker" Sifam ' ; in perfect order. Price 45/-,post free.

MODELS FOR XMASA GOOD PLAN INDEED, IN TIMES WHENALMOST EVERY FAMILY IS LINKED WITH

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At home in the evening he tunesin the wireless-gets tired of it-then glances through a magazine-can't get interested. Finally,unable to concentrate on anything,he either goes to the pictures orfalls asleep in his chair. At theoffice he always takes up the easiestthing first, puts it down when itgets hard, and starts somethingelse. Jumps from one thing toanother all the time. _

There are thousands of thesepeople with " Grasshopper Minds"in the world. In fact, they are thevery people who do the world'smost tiresome tasks-and get buta pittance for their work. Theydo the world's clerical work, andthe routine drudgery. Day afterday, year after year-endlessly-they hang on to the jobs that aresmallest -salaried, longest-houred,least interesting, and poorest-futured !What is Holding You Back ?

If you have a " GrasshopperMind " you know that this is true.Even the blazing sun 'can't burna hole in a piece of tissue paperunless its rays are focused and con-centrated on one spot ! A mindthat balks at sticking to one thingfor more than a few minutessurely cannot be depended uponto get you anywhere in youryears of life!

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The tragedy of it all is this ;you know that you have withinyou the intelligence, the earnest-ness, and the ability that can takeyou right to the high place youwant to reach in life ! What isholding you back ? One scientificfact. That is all. Because, asScience says, you are using onlyone -tenth of your real brain -power.What Can You do About It ?

Here is the answer. Take upPelmanism now ! A course ofPelmanism brings out the mind'slatent powers and develops themto the highest point of efficiency.It banishes such weaknesses anddefects as Mind Wandering, In-feriority, and Indecision, and intheir place develops strong, posi-tive, vital qualities such as Opti-mism, Concentration, and Reli-ability, all qualities of the utmostvalue in any walk of life.

The Pelman Course is fullyexplained in " The Science ofSuccess." The Course is simpleand interesting and takes up verylittle time. You can enrol on themost convenient terms. Thebook will be sent you, gratis andpost free, on application to -day to :

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131 Albion House, New OxIord tit.,London, W.C.1


72 November, 1942

WAR BRINGS COMPLICATIONS ....but it also brings simplification !

For the present, Dunlop are concentrating

for cycling needs on the production of

an all purpose cycle tyre. Dunlop are

applying all their technical knowledge

and research to the production of

this war grade tyre. It's a good tyre

and you'll get good wear out of it.

ask your dealerfor the

DUNLOPcu e rupfroseCYCLE GRADTYRE

211, 313

.9E00 TRADS MARK

1)0PLOCK

REMEMBERI NIS HILO

On such hills as Porlock you need

brake linings that you can trust. Know

that your brakes are safe by fitting

Ferodo Linings - sure gripping even

in rainy weather, noiseless in action and

tough in wear. In country like this -

aee weathe4 BRAKE BLOCKS


November, 1942 THE CYCLIST 9

VOL. XI NOVEMBER, 1942 NO. 249

All letters should be addressed tothe Editor, "THE CYCLIST,"George Newnes, Ltd., Tower House,Southampton Street,Strand, London,

W.C.2.Phone : Temple Bar 4363

Telegrams : Newnes, Rand, London

Comments of the Month

The Roadfarers' ClubTHE need for an organisation represen-

tative of all sections of road users-pedestrians, cyclists, motor -Cyclist's,

and motorists-has existed from the earliestdays of cycling and motoring. There are manyexcellent organisations which represent each,and which have performed most valuablework in representing particular interests. Quiteoften, however, owing to opposing points ofview, their efforts have been brought to naughtwhen their various and opposite views havebeen placed before the Minister of Transport.

During the war most private cars willremain off the roads owing to the petrolrestrictions. This means that after the warall motorists will start off with clean licences,because freedom from endorsement for oneyear entitles the holder to a clean licence.Road policy had become tangled at the out-break of war, but the war, which has called ahalt in road travel as far as motor -cars areconcerned, provides the pause for us to laycareful plans for the post-war period so thatwe can start afresh, in an endeavour to remedysome of the evils, not the. least of which' isthe appalling accident rate. Regulations,prosecutions, fines, restrictions, pedestrian -crossings, speed limit, one-way streets,roundabouts-these are but a few ofthe experiments which have been triedby successive Ministers ' of Transportin unavailing efforts to make the roadssafe. It should be possible to have" Safety Fast " as well as First,withqut danger to slower and morevulnerable road users.

Objects

THE newly -formed Roadfarers' Clubhas as one of its main objects

the improvement of relations betweenall road users. Its membership, alreadypowerful and important, is byinvitation only, and by unanimousvote of its committee. It will meet todebate various road problems in anatmosphere free from controversy, andin a helpful spirit with the one desireof finding a solution. The club isnon-profit making, non-political, andits ranks are open to cyclists, motorists,pedestrians, motor -cyclists, all thosewho have achieved prominence, notonly in connection with the useof the roads but in connection withthe administration of the roads.There will not be a preponderance ofany particular section of road user.

Another object of the club is toprovide social occasions when themembers can meet and discuss mattersin which they are mutually interested.It will help to keep them together andto maintain their interest where for-merly they drifted apart and theirinterest has flagged. Those responsiblefor the foundation of the club founda ready response amongst those whom

they approached to become members, andwho' form the basis of the pool ofknowledge of road matters and road userswhich will be available to the membership.

The president of the club is Lord Brabazonof Tara, ex -Minister of Transport, ex -Minister of Aircraft Production, holder of thefirst British pilot's certificate, racing motorist,and a pioneer in many other directions.Early members include Lord Iliffe, LordPerry, the Marquess of Queensberry, SirFrank Newnes, Bart., Sir Harold Bowden,Sir Henry Maybury (another ex -Minister ofTransport), Sir John Laurie (Lord Mayor ofLondon), Major -General Sir Percy Laurie,Sir Cooper Rawson, M.P., Sir GeorgeBeharrel, Frank J. Urry, G. W. B. Wilson,Percival Marshall, Trevor T. Laker, C. G.Grey, Prof. A. M. Low, Harold W. Eley,T. W. Loughborough (Secretary of the Auto -Cycle Union), A. Percy Bradley (manager ofBrooklands track), J. A. Masters (secretaryof the M.C.C.), G. Geoffrey Smith, M.B.E.(managing editor of Iliffe's), A. G. Reynolds(international timekeeper), A. V. Jenner(Charlotteville C.C.), Arthur Whinnet, C. A.(Bath Road) Smith, J. Dudley Daymond,

Lord Brabazon of Tara, President of the Roadfarers' Ciu'.

By F. J. C.

W. G. James (only living founder member ofthe B.R.C.), G. L. Samuelson (secretary of theRoyal Automobile Club), Frank H. Bale,O.B.E. (Order of the Road), A. H. Bentley, E.Coles -Webb, F. Peters Wood, J. F. Callway,F. J. Camm (editor, Tan CYCLIST), BobCarlisle (competitor with Hume at the firstbicycle race where pneumatic tyres wereused), Stanley Baron, Major H. R. Watling, J.P.(director of the British Cycle and Motor-cycle Manufacturers and Traders Union,Ltd.), T. D. Bell, J. F. G. Westaway, T. D.Osborn, J. R. Osmond, W. Hinds, V. S.Bowman, Frank Smith, Lewis Stroud,S. M. Vanheems, Lt. -Col. Charles Jarrott,0.B.E , W. J. Mills, J. E. Rawlinson, H.Scotto, C. A. Harvey, and many others.

The club is a national, not a local institution,and the secretary is R. A. West, 32, Elm -bank Gardens, East Sheen, S.W.13.

The Inaugural Dinner

THE club held its inaugural dinner at theClarendon on October 9th, with Lord

Brabazon in the chair. It was a memorableevening. Lord Brabazon, responding to the

toast of The President (proposedby A. Percy Bradley), said thatthe war has shown us great advancesin transportation, but motoring, insteadof advancing, has been in reverse.This war will give us a chance to startagain. We shall have the plans and thedetails ready for making a people'scar after the war. Just as Henry Fordstarted one revolution in transport, asecond revolution is long overdue.People should not be obliged to stayin congested areas. We desire in ourhearts, he said, that all-motorists,cyclists, hikers-should be free totravel far and wide over the roads ofour country in safety and in enjoy-ment. The Roadfarers' Club doesnot favour any particular section. Itis, he said, a remarkable club in thatit unites all the road interests. Speakingwith great sincerity he said that theclub was long overdue. The toast ofThe Visitors and The Press was pro-posed by Sir Frank Newnes in a neatand witty speech, eliciting a humorousreply by the Marquess of Donegall.

The toast of The Club was pro-posed by J. A. Masters, with a responseby the editor of this journal. Nearly70 members and guests were presentat the dinner. The guests includedW. J. Bailey, Leonard Ellis, H. Boon,Capt. F. C. Day, E. J. Appleby, PeterHunter, H. C, North, Charles C. Drew,W. H. M. Burgess, A. T. Bradford,H. J. Morgan, Dudley Noble, T. M.Craft, H. Payne, and D. . EllisJones. All of the daily newspapers sentrepresentatives. Thus this importantclub is launched and a great deal morewill be heard of it.


10 THE CYCLIST November, 1942

PARAG RA

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Hostel Still OpenTHAXTED Hostel, in Essex, is still open to members,

despite rumours that it is closing.

Timekeeper for ForcesJAMEST RIDDELL, Ivy C.C., has had his medical

examination and expeetS to go in the Forcesshortly.

Lord Keith's New PositionLORD KEITH, an official of the Scottish Y.H.A.,

is chairman of the Scottish National Parks Com-mittee.

After the War'I'HE Scottish Y.H.A. has several sites and buildingsA earmarked for post-war development as youth

hostels.

Closed for Winter-'`WO hostels in the London region have closed forA the winter. Th4 ire Ide Hill and Stony Stratford.

Better MapsTHE Ramblers Association has suggested various

4, improvements for future editions of the r -in.Ordnance Survey maps.

Armour Beats HartleyTJACK ARMOUR, the Fifeshire miner, rounded off

his 1942 Scottish successes by winning the Man-chester and District T.T.A. 25 on his first visit toEngland. Armour's time oft hr. 3 mins, 36 secs. was16 secs. faster than that of D. K. Hartley, best Man-chester man of the year.

Soldier's EnthusiasmALTHOUGH serving with a Signals unit in Scotland,

and unable to cycle except in Army clothing,Jack Baxter, of the Cyclists' Touring Club, LeedsSection, Mid -Yorkshire D.A., is still a keen tourist,and has visited many of the famous places in the LochLomond and Trossachs district.

Scottish Clarion MovesWAR -TIME :conditions may bring about a new

unity among Clarion' members in Scotland.The West of Scotland Union of the NatiOnal ClarionC.C. is to investigate the possibilities of linking withthe Mid -Scotland Union. ' Such a joint union wouldgive Scotland one of the leading places numerically inBritain in Clarion circles.

Youth Centre for GlasgowTIOSTEL officials on Clydeside are looking for a1. A building to replaCe the existing Glasgow youthhostel. They desire a building more centrally situatedthan the present hostel, which is at Cathcart, four milessouth of the centre of the city. It is proposed to use thenew hostel as a youth centre in addition to an overnightsleeping place.

Bigger Handbook?OFFICIALS of the hostel movement in Scotland

ate hopeful of increasing the number of pages inthe x943 hostels handbook.

Higher Hostel FeesTN future all youth hosteler's. over 21 years of age areA to pay 5s. as annual. membership fee. Formerlyonly those over 25 paid ss.

Most Popular HostelTHE most popular hostel in Scotland during 5942A is Loch Eck, in Argyllshire ; it hill been visited

by more than ro,000 cyclists and hiked.

Lakeland for TrustTWO further properties

in the Lake Districthave been acquired by theNational T r 0, Theyare at Kentinere and FarEasedale.

New LakelandHostel

CYCLISTS touring in'.' Lakeland next summerwill be able to use a newyouth hostel. This is Esth-waite Lodge, by the sideof Esthwaite Water.

More Beds forCyclists

QO popular is LedardLi youth hostel, close tothe Trossachs, that afurther 44 beds haverecently been added for theuse of cyclists and hikers.

Bicycles for Essential WorkersTT has been suggested that Britain should follow theA U.S.A. in granting permits for new bicycles onlyto workers who can prove that they need them forspecial transport.

Access. to Welsh SummitsMAXIMUM public access to the two Welsh moun-

tains of Cynicht and Moelwyn is assured by thepurchase of land including these summits by Mr.Clough Williams -Ellis, the architect,

Colchester's New HostelCOLCHESTER, in Essex, has a new youth hostel.

This is situated at Middle Hill House, in thecentre of the town, and has accommodation for 20.Another new hostel in Essex is at Saffron Walden.

Roman Remains at Chester111. EMAINS of a massive Roman building found at" Chester, one of the favourite haunts of touringcyclists, are believed to be the foundations of a wall ofa building on a site north of the line of the Romanfor -Was.

The Snowdon RailwayTHE Snowdon Mountain Railway, familiar to the

easy-going cycle tourist, has just completed oneof its most successful seasons. The railway was built46 years ago, and is the only one of its kind in Britain.

For National TrustTHE latest purchase by the National Trust is Taw

House Farm, in Eskdale, together with 215 acresof land. The position of the farmhouse is under thefoothills of Scafell and Bowfell, and the Roman Roadfrom Ravenglass to Ambleside passes close by.

New Scots HostelTHE Scottish Y.H.A. has acquired a new youth

hostel at Cove, on the Firth of Clyde. Volunteerworkers are renovating and equipping the buildingthis winter, and it is expected that the hostel will openat Easter with room for 80.

A Fast "30 "IN an open 3o -mile event held on roads east of London

" Jerry " Walters, South London C.C., not onlymade fastest time, but also secured three other awards.A good morning's work I

Prisoners of WarGASKELL, Rotherham Wheelers, and A. G.C Laxton, East Midland Clarion C.C., are among

the latest cyclists reported to be prisoners of warfollowing Middle East activities.

Team Race RecordTHE national 3o -mile team race record was broken

by a Clarence Wheelers trio (Messrs. D. Perrin,R. Watson and G. Royston), who aggregated 3.49.45,beating by is seconds the previous best.

Second Fastest 30 MilesTHE second fastest 3o miles ever to be recorded was

clocked by r8 -year -old Edwin Mundy, Addis-combe C.C., when he won his club's open 30 -milefixture with 1./3.38.

Finsbury Clubman's DeathSERGEANT PILOT JACK KEEN, Finsbury Park

C.C., formerly reported missing following anoperational flight over enemy country, is known to bedead. His body was washed up on the coast of Holland.

Scots Rider in EgyptCHAMFIQN of the Lomond Road Club for two years

prior to the outbreak of war, " Ginger " McCauleyis now With the R.A.F. in Egypt.

Club Members' MarriageDRENDA KAIN, daughter of " Jimmy " Kain," Ealing Cycling Club's gepial president, marriedSergeant Observer Jack Rodd, R.A.F., whose best manwas Bill Launspach, of the Royal Navy. All three aremembers of the Ealing C.C.

C.C. Polo Player Wins D.F.C.PRE-WAR member of Norwood Paragon C.C. polo

team, Pilot Officer Tom Stanley, R.A.F., hasbeen awarded the D.F.C. for gallantry and devotion toduty.

Canadian Rider's Death in ActionTN April Andy McConnell, the young CanadianA professional, delighted Paddington track farts withhis riding against Syd Couzens and Henri Auclair.News is to hand that Andy has met his death on active-service in this cpuntry while serving with the RoyalCanadian Air Force. He was buried at Newark,Nottinghamshire.

Veteran's " 25"ALTHOUGH within a year of his loth birthday,

W. J. Pett, national so -mile champion in 19os-6-7,rode 25 miles in 1.12.45.

Popular Time TrialsOVER 30o time trials, the majority of which attracted

the full quota of too riders, were held during thepast season. Many were " 25's," but semi -long distanceevents had reasonable support.

Southgate C.C.'s TrophyTo commemorate the club's diamond jubilee the

Mayor of Southgate (Cr. T. J. Oldland, J.P.) haspresented Southgate C.C. with a perpetual trophy, whichwill be handed over at the club's lunch at Cockfosterson Sunday, November 29th.

Cyclists v. Harriers EventTO signalise the opening of their 64th cross-country

season Finchley Harriers are arranging a cyclistsv. harriers event with the Westerley Road Club andthe Dragon Road Club.

Club Secretary MissingFRED FEW, former assistant secretary of the

Hampshire Road Club, is reported missingfollowing air operations over Malta. He was a R.A.F.wireless operator, and hopes are entertained that hewill prove to be in Italian hands.

Girl Rider's Fast " 30 "BY clocking r.24.17 in the Rookery " 30 " Eileen

Jordan, Addiscombe C.C., beat the ladies' 30 -milecompetition, and, of course, made the fastest time inthe event.

Champion Cylist With Fleet Air ArmONE-TIME champion of Crouch Hill C.C., and now

with the Southgate C.C., A. C. Elliss, who putup some fine short -distance rides, is now with theFleet Air Arm.

Consistent Short -distance RiderONE of the most consistent short -distance experts of

recent years is Jack Simpson, Barnsley C.C., who,in five consecutive 25 -mile events, clocked less than 6rminute but always just outside the coveted hour.

49 Riders in Open " 3o "NO fewer than 49 riders from a field of 5o finishers

beat their previous best in an open " 3o " recently.The morning was exceptionally fast.

Another WeddingMISS M. ROBERTSON, promising member of the

Rickmansworth C.C., has married Pte. V. Western,R.A.O.C.,er who, before joining the Army, was a keen

Stole 62 BicyclesATWENTY-YEAR-OLD Army deserter, Ian

McGillivray Coutts, was sent to Borstal for threeyears at Glasgow Sheriff Court when he admitted steal-ing 62 bicycles from various parts of the city. It wasstated in court that Coutts was found loitering sus-piciously outside a public library after machines hadbeen stolen from such places on previous occasions.

Coutts sold most of the bicycles to a dealer, and thepolice found at the dealer's premises a large number offrames and fittings which were later identified as beingstolen. Altogether the value of the cycles amounted to£321, and only £26 had been recovered.

More for PostcardsTHE charge for picture postcards of youth hostels

has been increased from 2d. to 3d.

Rubber Plans in StatesTHE United States has a programme for synthetic

ther endubberwlii,ic4hembodies the aim of r,000,000 tons

Grant for Civil Defence BicyclesQENIOR Fire Guards and Civil Defence wardensS

have been granted 3s. 6d. a month for cycleupkeep in full-time use, and 2s. 6d. part time.


November, 1942 THE CYCLIST - 11

A corner of thefamous old WhiteHorse Close,

Edinburgh.

Around the

for many years andcompares with 618 inthe same month of1939.

While the total num-ber of persons killedhas decreased since lastyear, the proportion ofchildren killed has risen.One out of every fivepersons killed in Augustwas under 15 years ofage, and the total num-ber of fatalities amongchildren in the thirdwar year was 1,309.These figures shouldbring home to everyparent the danger ofallowing small childrento use the streets withoutsupervision. They arealso a reminder todrivers that althoughtraffic to -day is so muchlighter, it is stillnecessary to make fullallowance for the impul-siveness of children.

N.C.U. Monthly CircularTHE National Cyclists'

Union is preparinga monthly circular ofN.C.U. a n d generalcycling news for des-patch to cycling membersof His Majesty's Forces

WheelworkBy ICARUS

Signposts to be Restored

' HAVE never supported the panic arrange-ments which were made during the early

days of the war, and which included theremoval of historic signposts and milestonesin the mistaken belief that an inva:,;imi wascontemplated, and that the Germans wouldnot be able to find their way around the

. countryside without them. It is my ownview, but I sincerely believe that an invasionwas never contemplated and that it will nevertake place. Now Mr. Noel Baker has an-nounced in the Commons that signposts areto be restored within certain limits andsubject to certain conditions. Such restora-tion will also restore some of the pleasures ofcycle touring, and will make travelling atnight, when there are few people on strangeroads from whom to inquire the way, a littlemore pleasurable.

Road Accidents

DEATHS from road accidents in the thirdyear of the war totalled 7,693. This is

nearly 2,400 fewer than in the second waryear, hut still substantially higher than in thelast year of peace.

An interesting indication of how peoplehave adapted themselves to the black -out isafforded by the fact that road deaths duringhours of darkness have declined from 4,503 inthe first year of war to just over 3,000. Thereis still need for much more care, however,and with the approach of another winterdrivers and cyclists are again advised to lookto their lamps and ensure that they are ingood condition.

The improvement in the road accidentfigures dates from 12 months ago, and wasparticularly marked in June,July and Augustof this year, a period which coincided withthe laying -up of many private cars. Thetotal of 502 deaths in August is the lowest

serving abroad. If, therefore, you have a friendin the Forces who would like to receive a copyof this monthly newsletter, please send hisname and address to the Secretary, 35, DoughtyStreet, W.C.I.New Road RuleCYCLISTS turning left can now signal the

fact with the left arm fully extendedinstead of by a movement of the right hand.

The old signal did not give a clear enoughindication to oncoming traffic whether thecyclist was about to turn right or left.

The National Committee on Cycling hasbeen informed by the Ministry of WarTransport that a formal amendment of theHighway Code incorporating the principlenow officially accepted will be borne in mindwhen it is revised after the war.

J. W. Bryan Memorial FundWITH the passing of John William Bryan,

of B.S.A. Cycles, Ltd., we have lost,one of the most prominent figures of ,the cycleand motor -cycle industries.

A wish has been widely expressed by manyof his friend& and those with whorp he wasassociated that a fund should be establishedto perpetuate the memory of such an outstand-ing character, and one who has done muchin the interests of the allied trades. A smallcommittee has therefore been formed and hasdecided to make an appeal for a minimum of£5,000 to establish a " J. W. Bryan MemorialFund." It is intende:1 that this fund beadministered by trustees appointed by thecommittee and to apply the fund in suchdirections as the trustees may decide, but thatif circumstances are found to warrant it, firstconsideration shall now or at any future timebe given to the needs of the family of the lateMr. J. W. Bryan, with the eventual objectivethat the fund shall be devoted to the benefitof the Motor and Cycle Trades BenevolentFund or any other charitable institution.

Everyone concerned in the allied industrieshas benefited in some measure by the genialservice J. W. B. gave to the trade over a periodof 35 years, and his strong personality, com-bined with a high plane of happy friendliness,attracted and retained the affection and confi-dence of a wide circle of friends. At the timeof his death he was president .of the BritishCycle and Motor Cycle Manufacturers andTraders' ijnion, Ltd., and chairman of theMidland Centre of the Motor and CycleTrades Benevolent Fund.

Subscriptions should be sent to GilbertSmith, Norton Motors. Ltd., BracebridgeStreet, Birmingham.

R.R.A. NewsTHE following records have been approved :

Portsmouth ,and back, tandem tri-cycle, G. E. Lawrie and R. Morford, in7 hrs. I min. 52 sec., on June 21st, 1942.

Bath and back, tandem tricycle, G. E.Lawrie and R. Morford, in to hrs. 5o mins.34 sec. on July 26th, 1942.

Bicycle StealingTN The Times recently there has been

correspondence on the growing menaceof bicycle stealing, and the Solicitors' Journalrecently gave a digest of the various pointsof view

" The increase in the use of pedal cycles isbringing into prominence a question whichuntil recently enjoyed comparatively littlepublicity, namely, the stealing of bicycles.In the course of a correspondence in The Timesextending over the week from July 16th to23rd, a number of eminent authorities tookpart in a sort of written symposium of the bestmeasures to counteract the evil. Sir EllisHume -Williams thought that every bicycleshould have attached to it a licence and aname and address plate, and this suggestionwas supported by Mr. C. B. Marriott andSir Archibald H. Bodkin, the former on theground that it would greatly"help the policein their investigations, and the letter on theground that it would facilitate proof of larcenyas the removal of the registration plate wouldclearly indicate intention to steal. By wayof opposition, Mr. Eric J. N. Nabarro pointedout that the system had been found wantingin Holland, as a licence plate was removablewith a sharp knife. Mr. G. Herbert Stancer,Secretary of the Cyclists' Touring Club,argued that licensing would involve anelaborate and troublesome system of transfer,and that bicycles could be rendered unrecog-nisable by being rebuilt with interchangeableparts. He pointed out that the best safe-guard was to lock the machine and removeaccessories such as lamps and inflators, whereit was left unattended even for a short time.Sir Archibald H. Bodkin pointed out that agreat part of the mischief arose from wrongfuland unauthorised borrowing. The questionwas whether this amounted to stealing, as itwas difficult in such cases to show that therewas any intention permanently to deprive theowner of his possession, so as to satisfy thedefinition of ' stealing' in s. t of the LarcenyAct, 1916. He said that a similar positionarose in regard to motor cars, but by s. 28 ofthe Road Traffic Act, 1930, it was made anoffence to ' take and drive away any motorvehicle without the owner's consent orwithout lawful authority.' He thought that ashort Act of Parliament was necessary,providing that the words ' motor vehicle ' ins. 28 should include pedal cycle.' It isinteresting to note that in an answer by Mr.Peake to a question in the Commons onJuly 29th, it was stated that the question ofamendment of the law was being looked into.There seems little substantial ground forcriticising either the licensing proposal of thesuggestion as to the amendment or the law,but the experience of most cyclists is that astout padlock is their best safeguard."


12 THE CYCLIST November, 1942

Lakeland. -A stop by Cr.ummock Water. In the middle distance rise the twin peaks ofWhiteless Pike.

WHAT hard work some of the newcomersto the ranks of cyclists make of their

riding ! Their energy is praiseworthy in-deed, but some of them have not realisedthe fact that there is a right way to ride abicycle, and that balance, correct pedalling,and a proper sitting position are essentialsto real cycling joy. There is more to thebusiness than just buying a bicycle, sittingon the saddle and pedalling hard ! Thesethoughts come to me as the result of watchingmany riders recently-many of them riderswho have taken to cycling afresh after yearsout of the saddle. Some I watched from anold stone bridge not far from Kenilworth.My companion an " old stager " whocontinues .to extract tons of joy from cyclingdespite his 65 years, and he watched theprocession of riders with me, took his pipefrom his mouth, and muttered somethingabout the need of lessons in riding. Well,theremay be something in it, but, anyway, Icommend those cyclists who, in these war-time days, are riding for the first time, orhave taken up cycling again after years ofmotoring, to buy and read one of the littlebooks which can be obtained, and which dealwith the whole art of riding. It is worthdoing, and added riding joy will result fromdoing the job in the right way.

Famous Old-time CyclesRECENTLY I mentioned the names of

famous old-time cycles, and' I havealready recorded that the mention broughtme quite a lot of correspondence. Well, Iwas thinking the other day of famous tyrenames, and I recalled that in the very earlydays there was a cycle tyre named the Clifton.I fancy it must have been one of the veryearliest makes-popular at the, time when theDunlop patent was the subject of almostconstant litigation. And I remember, too, theKempshall-a cycle tyre made by theMacintosh people. Not so many makesto -day, and my dealer tells me that theBates range of cycle tyres has gone-at anyrate for the duration. We live in an age ofstandardisation and simplification, and wemust be content with the War -grade " tyresoffered by the several manufacturers. Solong as there are tyres to enable us to keepon riding, I for one shall not grumble.

Hobbies.ONE of the grand things about cycling is

the number and variety of interests andhobbies which can be easily combined with it.For my own part, my cycle has always linked

up with my interests in nature -study, and mycollection of butterflies, and moths was onlymade possible because I have been able to cycleout to those districts where I wished to huntthe specimens ; and this summer pleasantrides out to heaths and commons haveresulted in many additions to the collection.

CycloramaBy H. W. ELEY

time and accepted it without a grumble, itseems strange to recall the fierce controversieswhich raged for so long over the originalproposal to introduce the one hour's extradaylight. Willett was a persistent crusader,and won his long fight. And, taking thematter broad and large, I fancy that the nationregards summer -time as a boon-thoughthe farmers may occasionally voice theirgrumbles ! The " Daylight " at Petts Woodis a handsome structure, architecturallypleasing, and is the social centre of the suburb.

Inn SignsTALKING of inns and inn signs, I wonder

why cycling and cycles have not beenmore greatly featured ? Where is our" Wheelman's Arms " ? Or where do wefind " The Tandem Inn " ? The inn is of theroad-and so is the bicycle. It seems passingstrange that cycling has not named more innson our highways. Old coaching days arecommemorated by hundreds of inns bearingsuch names as " The Coach and Horses."The coming of the iron road brought a cropof " Railway Taverns " and " Station Inns."It may be that the cycle is immortalised by

Famous Old-time Cycles : Hobbies : Tribute to William

Willett Inn Signs : Cyclists' Red Cross Appeal

Often it is too far to walk to the haunts of theFritillaries, the Blues, the Commas, and theSmall and Large Coppers-but the cyclesolves the problem. And if there is onesummer -time delight I love it is to be on awide common, butterfly -net in hand, andwatch for the " specimens," which flit aroundthe rag -wort and the scabious, and those otherplants beloved of the winged creatures whichsome of us covet as a miser covets gold.

Tribute to William WillettBUSINESS took me to Kent the other

week, and I found myself at Petts Wood,not far from Orpington. Fittingly, the innthere is called the " Daylight "-a tribute toWilliam Willett, born, I believe, in the place.To -day, when we have had double summer-

eropksbury Kill.Auiew of t,o well known.

Surrey beauty spot and

.4r4, NsZa.A

isNirna,-40

more inn signs than I know, and I should begreatly interested to hear from readers onthe subject.

Cyclists' Red Cross AppealT HEAR good news of the Cyclists' Red Cross

Appeal, and I was glad to see the advertise-ments recently featuring the aims and objectsof the appeal. In the realm of sport generallyvery fine help has been given to the Duke ofGloucester's fund, and one always knew thatcyclists would not lag behind the golfers, thetennis players, the footballers, and the boxers.The total is growing nicely, and if everycyclist responded to the appeal the resultwould be grand indeed. There are a lot ofus-let us see to it that we play our part. Theneeds of the Red Cross are great and pressing.


November, 1942 THE CYCLIST 13 ,

MakeA Permanent Fitting Device

THE fitting shown in Fig. 7 consists of apiece of zin. strip metal about 8in. long,and bent into the shape of an inverted U,

with the eyelet at the top. At each end of thestrip a hole is bored. A small bar with a knobat one end and a hole to take a small padlock atthe other is then required. To assemble thedevice, clip the metal U over the front mud-guard close to the fork, bolting it to the forkwith the same screw as used for the mudguard,thus making it a permanent fixture. To lockthe cycle, push the locking bar through theholes, which should just miss the rim, and thiswill prevent the cycle from being moved.

Locking the Front ForksThe simple gadget shown in Fig. 8 prevents

the front forks from turning when the cycleis standing up against a kerb. Drill a 116 -in.

hole at the centre of the head, with thehandlebars turned slightly left. Insert a pegto hold the steering fixed. The peg should beenamelled the same colour as the cycle.

Steering -head FixtureA 7/32in. hole is drilled at the centre of the

steering head and a springy, partly circularclip, the diameter of the head, is made with a.j in. peg riveted near each end. When this isplaced around the head each peg enters a

00 -

Eyelet rweteoon U -piece

About4"

Locking Bar

Fig. 7.-This device is a permanent fitting to thefront forks.

hole, and holds the steering in a fixed position.The pegs, of course, should be diametricallyopposite. (Fig. 9.)

Back Brake LockIn Fig. to is shown a fitting for holding the

back brake in an " on " position. When thebrake has been put on, a padlock is slipped

Fig. 8.-Making therant fork unmovable

Your Bicycle Thief -proofFurther Effective Methods of Circumventing the Cycle Thief

(Continued from page 4, October issue)

through one of the holes in a plate attached tothe brake -rod near the bottom bracket, andthis holds them on against another bracketattached to the chain stays. The brakescannot be released except by removal of thepadlock.

Riveted Pin orSmall Bolt

Fig. 9.-Another ingenious devicethe steering head.

-11 Several holes'Position °f I for adjustment

I I Lock when1 I

- Brake Is onL -

Fig. IC).-A fixture for holding the back brakein the " on" position.

or locking

To Brake

no key. It can be fitted in a short time, andcan only be opened by someone knowing thecombination.

Another Wheel -locking DeviceThe idea shown in Fig. 12 is an improve-

ment on the cycle lock and chain. The position

Fig. I2. -A strong wheel -locking device.

is at the back stays, as shown. On one side isan eye (A), which is permitted to swivel, anda shaft (B), with a head one end and a holedrilled in the other, passes through this eyeand another (D) on the other side. Fixed tothe shaft is a collar (C), either welded onwhen the shaft is fitted or fixed by a set screw.This is to prevent the shaft from falling outwhen not being used. When the shaft ispassed through the eye D, which is weldedon the frame, a small padlock is used throughthe drilled hole to keep it fixed. When the lockis not in use, the shaft is secured to the stay

Combination Lock ScrewThis thief -proof lock comprises a clip and

combination lock, which is fitted to the headof the machine, as shown in Fig. ir, and locksthe steering. A hole about a lin. or, isdrilled through the frame and fork stem,while the handlebars are straight, and the lockclipped on, so that the bolt is in line with thehole. The device is self-contained, and requires

Fig. 11.-A com-h i nation locking

Tappedlug

Bracket

Metal lugbrazed to am

Bracket brazedto fork

Tin band(Soldered)

Fig. i3.-An unusual method adopted to securefront wheel.

Wire key

by a spring clip. (E). This improvement onthe cycle lock and chain is that the cycle thiefcannot easily snip the rod with a pair of pincersas he can the chain.

Bolting Fork to RimA piece of metal, tapped as shown in

Fig. 13, is brazed on to the front rim, and abracket tapped similarly is fixed to the frontfork, the hole corresponding with the firstbracket when directly behind it. A bolt isthen used to lock the two together.

The bolt chosen should have a roundedhead, then if two small holes are drilled inthe head a small key made from wire will bethe only means of locking it. A lock of thisdescription may be fitted to the front or backiOrk, and also on the right or left.


14

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ThIt CYCLIST November, 1942

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MNMK

Right Out of Date1" SUPPOSE a day will arrive when authority at theA War- Office will discover the military bicycle is atleast 3o years out of date. Think of its specification :24.in. frame, 28in. x I kin. tyres, 12in. bracket, and, ontop of all, a big saddle, which makes the reach beyondthe comfort of a soldier of meagre inches. And, in any

- case, only a giant can drop his foot and still remain inthe saddle with one foot on the ground, and, in myopinion, that is a necessity in these traffic -ridden timesof road travel. We know how soldier -cyclists regard themilitary bicycle, and we hear that the average user of it(not being a consistently regular rider in civilian life) hatescycling as a result of exercise with this real abortion inbicycles. I happen to know that many of the makerswith Government contracts for military machines haveprotested that the pattern is archaic ; but it makes nodifference ; there is the specification, take it or leave it.I can understand that a military bicycle must be sturdilymade, for it has to go through hard times, but that isno reason why it should be awkward and far heavierthan needful to undertake the rough work which willsurely be its lot. A 22 ill. frame and 26in. x din.wheels would give a low bracket of I °fin., be a strongerand more serviceable mount, considerably lighter thanthe present model, and would comfortably accommodatethe leg length of every soldier in the Army. Such aspecification geared to 63in. would make Militarycycling comparatively easy ; but perhaps the Armyauthorities don't want the soldier to ride easily !Anyhow, the current model moves one to form thatconclusion, or the more deplorable one that the folk inauthority know just nothing about cycles or cycling.

A Step ForwardJWROTE the foregoing paragraph a few days ago

after seeing a consignment of military bicycles just..ready for delivery, and listening to the criticism of themaker. To -day I saw another military machine designedand patented by a famous firm, which I am very glad tostate brings the story up to date. I am not allowed todivulge details, but I think you can take it that thisspecial bicycle, designed for a special purpose, willrevolutionise the War Office notions on cycling. Onecan say this, however, that the machine only weighs27ilb., has 26in. x din. wheels, two brakes, a decentsaddle, and folds into a form easily carried on the back-the folding device being the strongest, lightest andsimplest I have seen. I do not think this design willbecome the standard military pattern, but its introduc-tion to the special military service for which it is beingmade must open the eyes of authority to the fact thatthe present standard pattern is just a handicap to manyA rider, instead of a help and convenience.

Get AheadTHIS special machine goes to prove that cycle

design and construction has an ample field stillleft for exploration, and I, for one, hope the manu-facturer will exploit such possibilities immediately this

war has ended, and not,as they did after the closeof World War No. x, waitfor the " Continental"designs and innovationsto get ahead of us. Thatsuch was the case in theearly years after the lastwar there is no depying,for right up to the startof this conflict " Conti-nental " pattern or type -

was a phrase in commonuse to describe a verymodern British product.The best bicycles in theworld are made inBritain ; let us see thatthey are also the bestdesigned, and not fightshy of the alterations thatare bound to be intro-duced. If you and I ateto get the very best outof cycling we do not wantstabilised design - wewant improvements.

Worth Attention .

THE war -time bicycle is not quite as good as thepre-war model of standard type. I may get into

trouble with my trade friends for stating that opinion, butI believe it to be true ; nor is it remarkable because,like therest of the manufacturing world improvisationshave to be undertaken; only the best of everything isused for the Forces, and no one will complain about that.We are lucky to be able to buy bicycles, and the possi-bility is that before this trouble is over the supplies willhave dribbled away to vanishing point. Winter willsoon be with us, and if we want to make certain of ourcycling convenience and occasional pleasure trips, itis more imperative than ever that we care for ourproperty. Lubricate and adjust ; give the machinefive minutes a week, it deserves that attention in ex-change for its services-but how rarely it gets it. Ithink the most common form of maladjustment is theloose crank, for it advertises the fault with its everyturn, and it is remarkable to me that so many riders'seem ignorant of the cause of the regularly recurringsqueak. Unless the crank is forced on to the axle key-way, and the -locking -nut tightened, both axle and -cotter -pin are in danger of wearing beyond repair, and neitherof them is easily replaceable these days. That faultadvertises itself ; but slack bearings and faulty brakes

WAYSIDE THOUGHTSBy F. J. URRY

I Like 'a ComradeTOWARDS the end of

A August 'I met afriend in Welshpool whowas just completing aweek's tour, and who saidhe had thoroughly enjoyedthe break, although he hadbeen " on his own."There are, of course, manypeople who can travelalone and enjoy everyfurlong ; but I confess Iam not of that self-con-tained happy kind. Iwant someone with whomto share the beauty of thescene, the ease or ardourof the journey, and thenI think it is doubly

enjoyed, yes, even the difficult bits, particularly inretrospect, over the pipes and tipple at the endof a long day. After solitary riding --and especially three lonely evenings-I yearn for thecompany of someone who needs no wooing to friendship,and even the solace of a good book does not fill the gap.Perhaps I happen to be a particular species of gregariousanimal, and suffer from a lack of conversation. And Ifind this, too, that the urge to get on with the journeyingwhen there is no need for it, is a common habit with thelonely rider. He had no one to check this curious desireto hasten, or perhaps it would be more ttue, in my case,to say I have no one to check and suggest a smoke insome delectable spot past which it is a sin to rush.Then there are those little adventures along stony lanesand over hill -crossing that do not seem worth while tome as a lonely rider, but how joyful they are when theexploration is shared. The loneliest time, however, isin the evening, when the day's journey is ended, one iscomfortably fed, and the aftermeal stroll is deprived ofthe summing-up of the good day which I feel wouldhave reached perfection had its delights been shared,discussed and tucked away in two memories instead ofone. I admit it is not always easy to find the rightcomrade whose leave synchronises with yours (particu-larly in these days), bin in this matter I have beenfortunate for many years, and though, as I grow older,arrangements present greater difficulties, I havemanaged to overcome them up to the moment, and Iam living in the fond hope that they will ease when thiswar is over and this strain of anxious dayspast

Riding RightlyEVERY, cyclist must know of friends or relatives

who, having taken up the pastime because theycan no longer use a car, are riding awkwardly andputting an unnecessary strain on themselves, forwhich they are blaming the bicycle or the game forwhich it is built. Because such people are disgruntledwith the imposed restrictions on petrol they are notprepared -to give cycling a fair chance to do a happyjob for them, certainly at a reduced speed, but alsowith the addition of a healthy exercise, and the oppor-tunity to absorb the beauty of the countryside. Suchpeople are difficult to advise, and some of them evenresent the suggestion that they would improve theease and comfort of their progress awheel if they adoptedcertain altelations. Often enough I find resentmentof such friendly advice arises from the idea that be-cause the dealer in selling them the machine said thatit was specially suitable to their make and build, theyfeel the amateur adviser is wanting in experience.When I drop across this form of resistance I alwaysask the individual how often-if ever-he has seenthe dealer riding his own wares, and suggest that a trialof my advice casts nothing and can be treated as a trial.It invariably works and makes a better cyclist and, whatis more important, sometimes an enthusiasticone.

. are only, known to the rider or to the person examiningthe machine. Such carelessness means wear, uncom-fortable and sometimes dangerous riding, much, if notall, of which can be cured by the intelligent use of aspanner. Correct adjustment is more important -thanever, and because quality is not quite so -good as threeyears ago, the need for it is likely to occur more fre-quently. Keep the chain at the right tension, pumpthe tyres hard, and oil all bearings and chain every twohimdred miles, or a trifle more frequently if. the weatheris bad. Do these things regularly-'7and they take solittle time-and you will ride easier, your bicycle willlast longer, and hold-ups on the daily journey will bereduced to a minimum.

A Fine CountrycONSIDERING the times, I have been fortunate`--4 in my wheeling freedom during this rather sunlesssummer. Early in August I spent a few days with anold frend in Galloway, that south-west corner ofScotland that has been, for so many years, tourist -neglected, for the visitor to the north is usually in such arush to reach the highlands that he neglects to see thehills and lochs and fine sea margins of the shires ofKirkcudbright, Wigtown and Ayr. Most of our wan-dering con this occasion was concerned with the formershire, with the end of the run touching the border-lands where the Esk runs in beauty, for we had not thetime for a prolonged stay, and no inclination to force thepace. Only once did we encounter the slightest difficultyin finding accommodation, and that was when weinadvertently stepped into the middle of a big militarymovement ; otherwise we were made most welcomewith good plain food as our portion. When you havea cycling holiday in the offing, and desire a change fromDevon and Cornwall, Wales or the Lakes, think ofGalloway, and I am fairly certain you will be agreeablyentertained. Although there is climbing to be done,so well are the roads engineered and so excellentlysurfaced that little necessary walking is entailed, thoughover some of the passes I would be sorry not to lingerand more thoroughly absorb the loveliness. The valueof Galloway from a cycling point of view is that you arenever travelling in one direction for many miles, withthe result that a steady full-blooded west wind (as wasour portion) is as often with, as against you. The landis rather sparsely inhabited in some areas, and it iswise to carry lunch ; but if you are a hungry wanderer,this is a friendly land, and almost any shepherd'scottage will make you a simple, but very welcome meal.Yes, Galloway should be on the touring list of everywandering cyclist.

Wanted-More CareAM glad the big firms in the industry have seen fitto use what little advertising space has been allotted

to them in the daily press for the purpose of preachingthe value of care in the use of our machines. Suchpropaganda was, and indeed is, badly needed, for Ifirmly believe more bicycles are ruined by neglect thanare honestly worn out by travel service. That factwouldn't matter much (since people do as they pleasewith their own property), did it not naturally followthat the neglected machine is often hard to ride, is arattle -box devoid of all sense of pride in ownership,and is no compliment to the splendid pastime it shouldencourage. The net result is that the average ownerof such a property has nothing to say of cycling, andthe fact that the fault is wholly the rider's only makesthe matter worse in my' opinion. Belatedly the makerhas recognised that a well -ordered bicycle is a well -ordered advertisement for the transfer it carries ; andthis attempt through the channel of advertising toinstruct the careless how to oil and adjust the machineto obtain the maximum of comfort and joy from its useis timely. I have always felt that the first thing thatgoes to the making of a good cyclist is a decent sense ofpride in the possession of such a wonderful piece ofmachinery, and once ti at can be inculcated into themind of the user, the lit Y of enthd liasm for the pastimeis made far easier.


November, 1942 THE CYCLIST 15

St Mani Vi'Ts*

War 20.000isr affe.024

My Pointof View

bY WAY ,A,12E127 "awe .d"

-

'Oe

Adderblay (0..4

Wonderful !ALMOST my only comment on the recent announce-

ment of a radical change in the signal for cycliststo give when turning left is that our politicians, likeour policemen, are wonderful. If we go on at thisrate, I believe that we shall win the war!

Let's Be LogicalT NOTICED a few weeks ago that there had been aA renewal of the suggestion that children should bebanned from the public highways because of theaccidents. which happen to them. If that is the propercure, then may I suggest that, as burglars break intohouses, people should be prohibited from living inhouses. It sounds logical-and is rather better thanarresting the burglars !

Curious MentalityDESPITE the vast changes in traffic conditions, the

curious mentality of certain motorists remains.The ocher .day I sighted a specimen coming `towardsme well on his wrong side of the road. In accordaricewith plan, 1 therefore took up my position in the verymiddle of the road, just to show that I was equallyentitled, to the liberty he had annexed-this despite thefact that " cyclists don't pay taxes " 1 The motorist'sfirst reaction was to blow his horn at me. I ignoredthis impudent gesture and stayed where I was. Andthen, when he realised and adjusted his position on theroad, I, too, went to the left!

The Obvious Remedy''THE scene was a meeting of the Works Council

(which I attend by invitation) of the factoryat which I toil and spin, trying to earn enough moneyto enable me to pay my income tax. The questionunder discussion was one of holidays, and the timewas late summer.. Could not the factory hands, makesome arrangement whereby they might get away earlyon Saturday morning and thus avoid the crush character-ising railway stations in the afternoon ? A deadlockwas at hand, and then a voice said : " Mr. Chairmen,

would not the position be met if we all had bicycles ? "Everybody burst out laughing, and the chairman turnedto me with a benevolent smile, accompanied by theremark : " I knew you'd say that ! "-and then seriousdeliberations were resumed. But isn't it a fact thatif more of us had bicycles, and knew how to use them,it would be better for everybody ? Of course it is !

Which reminds me that one of the factory handsbuttonholed me a few weeks ago and complained of theunconscionable time he had to spend, now and again,on getting to and from his work. I listened sympa-thetically, and then said simply : " You ought to geta bicycle." He looked at me in amazement, as though

had made an outrageous suggestich, and then replied :" Do you know how much bikes cost in the shops ? "Actually, not having any time for looking in shop -windows, I was devoid of this information, but Iretorted that, whatever the cost, the money he saved

lin fares would soon adjust the matter, apart from thegreat saving of time-and the setting aside of incon-venience and ,annoyance. It seems to me that we inthis country have been so pampered through the mediumof public transport that the man in the street neverthinks of doing anything for himself. Yet the bicycle-the simple bicycle-solves all transport problems, atleast on a small scale, and provides the user with apleasant, inexpensive, convenient and always readydoor-to-door travel unit.

Cause and EffectTWRING the summer which has now departed-.-L.' presuming it ever came !-2 man who inquired ofme where.I was intending tospend my holidays was told"Wales." But, he objected, isn't it very hilly ? That;I rejoined, is a classic example of .cause and effect." Speaking generally," I went on, " It is quite hilly inWales. That is the cause Ve..ith FT(AILICRs the effect,and r..,...arlts in ra, cony( to %Vali-, often as possible.

The Cyclist and MusicIHAVE never heard it said that cycling and music

have anything in common, or any affinity for eachother, but it cannot be denied that many cyclistsitre musical. I have found that certain songs make aparticular appeal, and one at any rate was, and still is,extremely popular. 'That song i " The Road to theIsles," often sung by Sir Harry Lauder. The wordsare delightful and have a peculiar twist that leavessomething to the imagination and then satisfies. Thereis nothing hackneyed in these words. Unlike manyConks, it conveys a sense of atmosphere to the cyclistand can beidly fail to interest because of its geographicalstyle. In a sense the song is a tour and I am certainthat many a tourist has done in Scotland what othershaVe done after reading Robert Louis Stevenson-gone over the route to see for himself. The song is anostalgic yearning for the Cuillins, and who, havingonce seen these grim and forbidding peaks, can dis-believe that they can exercise a powerful pill! on thoseborn and bred in their view ? The song goes ontodescribe the route that the prodigal would take to getthere, and although there are many who would questionhis choice, he certainly gives us much food for thoughtand a suggestion for a tour.

-The Road to the Isles" 111( Tummel and Loch Rannoch and Lochaber I" will go." Such is the route our wandererchooses. I wonder why. , How does he get toTummel to begin with ? It is merely a small loch to thewest of the Pass of Killiecrankie. We must allow a lotfor poetic licence, but it would be interesting to knowjust why the long journey begins right in the heart ofScotland. Was he a sailor, tramping from Dundee, ordare we suggest that he was a cyclist, making his wayfibna the far south. I scarcely think so in view of the

The same cause operates as regards theCotswolds, the Scottish Highlands, andcertain parts of Ireland-with exactly thesame effect. Mind you," I added. " someof the slopes go up, and some go down,and, when you're walking uphill, there'susually plenty to look at in the way of finescenery." I do not know whether I con-vinced my friend that, broadly speaking,if you want the cream of loveliness you willfind it in a tilted land. , To say that is not,of course, to deny the beauty of (for ex-ample) the Cheshire Plain or the Vale of

York. Whilst I can always be happy there, or about theNorfolk Broads and the Fen country, and elsewherewhere the scenery has been flattened hut, the lure ofa mountainous district is very insistent and vocal to me.

New NameOWING to the fact that 1 no longer wear the black

stockings of the racing brigade (and also of someof the big road clubs), or perhaps because I am nowloitering more fiercely than ever, it is a long time since

the epithet " racer " (in some parts of the country"ricer ") was flung at me. But the other day, some-where in mid -Wales, my appearance in a village wasgreeted with the exclamation : " Coo ! Scorcher bike ! "I would not have thought that a bicycle with a verymoderatelydropped handle bar could provoke such--er--perspicacity.

Sound Advice'THE advice which is being handed out to us by tyreA. manufacturers and others, regarding the need for

lookitig after our tyres properly, is as good for normaloccasions as it is in these particular times,. when itbecomes really urgent. Correct inflation is vitallyimportant. A regular examination of covers in searchof foreign bodies displaying a desire to settle down thereis also important. A little care undoubtedly doesprolong the life of tyres, and may avoid a spot oftrouble at most inconvenient times. Another point :if an unusual sound is heard from one or other of thewheels, dismount instanter, and pick out that hobnailyou have just appropriated. Twice within recent monthsmy tyres have revealed an acquisitive mood, and oneach occasion I acted with sufficient alacrity to preventthe business end of a nail from " carrying things toofar " and causing a puncture.

BusybodiesSOME of these busybodies who like to clutter up

cross-roads and give gratuitous traffic signs causeme to have severe attacks of nausea. I saw one of himthe other day. His beneficent work was singularlyunnecessary, as he was encouraging traffic to disobey" halt" signs. As I went over the crossing-ignoringhis exercises so far as they w,ere supposed to concernme-I advised him to desist from interfering, havingregard to the fact that traffic had to come to a standstill,and that he had no right to encourage it to do otherwise.He gave me a look as black as thunder and told me tomind my own business-an injunction which wascurious when coming from one who was certainly notdoing so himself.

Notes of a HighwaymanBy LEONARD ELLIS

route that follows. From Tummel to Loch Rannoch wecan understand as a good road connects the two, andcontinues along and beyond the loch to Rannoch RailwayStation. Heaven forbid that our traveller deigned touse the railway-no, he says : "step I with my cromachto the road "-he must be walking. But where fromRannoch ? From the end of the road there is a wildand boggy stretch across the moor of Rannoch toKingshouse Hotel on the Glencoe Road, but if pathsexist over this wilderness I have never seen them. ToLochaber we see eye to eye, the description is so widethat he might choose any route, as Lochaber is a vasttract of country containing among other things BenNevis.

By Morar to the Sea'RUT if he goes direct from Rannoch to Ben Nevis" he must be following the. railway line. His nextjump is a mighty one-" By Shiel Water thetrack ik to the west, by Ailort and by Morar to thesea." Now we are bn familiar ground. We assume thathe took the well-known and well-worn road beyondFort William, alongside Loch Eilt, to Glenfinnan,where we find the Prince Charlie monument and thatglorious view down the length of Loch Shiel, or ShielWater. Alongside Loch Eilt and then across the headof Loch Ailort, and we can actually see the sea, withthe dumpy shapes of Eigg and Rum Isles away in thedistance. The road winds and twists and performs all_sorts of convolutions up and down and sideways, untilwe reach the sea before we get to Arisaig. The routeindicated in the song means a turn to the northwardalong the coast until we reach Morar. Here we are atthe head of Loch Morar. that pours its waters, in afine fall, into the sea, and along the seashore is astretch of dazzling white sand that is a landmark forthe Isles. Only three miles along is Mallaig, where aboat will take us across the Sound of Sleet, a stormylittle trip, and we step on to the Isle of Skye.

he Pall; ti/ Atorar. near Mali.,


16 THE CYCLIST November, ;942

QUERIES AND ENQUIRIES(Continued from page 69)

" The Seasoning of Woods" by T. B.Wagner.

" The Kiln -Drying of Timber," by H.D. Tiemann.

We believe that the Forest ProductsResearch Association, Princes Risborough,has issued one or two pamphlets dealing withthe artificial conditioning and seasoning oftimber. These can be obtained either fromH.M. Stationery Office, King Street, Man-chester, or direct from the Forest ProductsLaboratory at Princes Risborough.

Cloud IndicatorCAN you please give me some in-

formation as to the constructionof the instrument which gives the heightof clouds, and which forms part of the" Fitzroy " Barometer ?

Will you please tell me 'a) Whatsolution is used ; (b) Method of gradua-ting, (c) The principle of the apparatus ?

I recently purchased a whirling psy-chrometer, together with relativehumidity tables, but am experiencinggreat difficulty in obtaining dew pointtables. Will you please tell me how thedew point can be calculated from therelative humidity tables ? -Ron a IdBachell (BathfordTHE " cloud indicator " which you describe

is only a scientific toy, and, for seriouswork, is of no value. It does not actuallyindicate the height of the clouds but merelyvarious atmospheric conditions, the liquidprecipitating under certain pressures andstates of the atmosphere.

The liqqid has the following composition :-Camphor .. .. 21 drachmsAlcohol (Rect. Spirit) .. t tDistilled water .. . 9 ,,Saltpetre.. .. 38 grainsSal ammoniac .. 38 33

The above proportions must be closelyadhered to. Methylated spirit cannot beused in place of rectified spirit.

The camphor is dissolved in the spirit, andthe salts in the water. The two solutionsare then mixed and poured into the glassobservation tube. This latter is providedwith a tightly -fitting cork, well covered withwax in which a very fine hole is made.

The weather indications of this device areapproximately the following, and it is fromthese that the Fitzroy instrument essays toindicate the height of the clouds :-Soft and powdery

precipitate .. Rain, South-west winds.Hard, crystalline

deposit .. Northerly winds.Crystals on one side

of tube only .. Winds from that directionPrecipitate remains

at bottom of tube Fine weather.Precipitate gradu-

ally rises .. Coming rain.In winter -time, the precipitate is usually

higher in the tube than in summer -time. The device is simply an atmosphericpressure apparatus, the atmospheric pressurealtering the physical content Of the solution.

There is no direct formula for obtainingthe dew point from the relative humidity ofthe atmosphere, since the dew point is atemperature, whilst the relative humidity isthe expression of a ratio existing betweenmasses of water vapour. For practicalpurposes, dew points are obtained by directexperiment by means of Daniell's or Regnault'shygrometers.

A practical book on this subject whichmight be of interest to you is : " PracticalExercises in Heat," by E. S. A. Ronsob.(Macmillan & Co.)

Model Electric Railway WorkingIHAVE a transformer output (18, 12

and 6 volts, 5 amperes, 5o cycles),which I use for a model railway, andaccessories. Relays, however, do notwork at all satisfactorily, as there ismuch sparking and noise. Consequently,I wish to use a rectifier. I have tried aNodon valve but with little result. Wouldyou therefore advise me on the followingpoints :-

(z) What is the best kind of rectifier touse, if current losses are to be keptsmall, the rectifier not to cost more thanabout 3os. ?

(2) Where can I get such a rectifier ?Or, is it possible to make such a rectifierwith materials obtainable at the presenttime ?

(3) What other components must beput in the circuit in order to obtain asteady current, and where can I get these?-K. B. Everard (Alford).THE relays and any other apparatus de-

pending upon magnetic action willalways be somewhat noisy if supplied withalternating current, but the " chattering "effects can be done away with by rectifyingto D.C. It is unlikely that you will be ableto purchase a dry rectifier of the " copper -oxide " or the selenium " types for thefigure you name, but you might apply to theBritish Westinghouse. & Saxby Signal Co.,Ltd., York Road, King's Cross, N., or toCrypton Equipment, Ltd., North ActonRoad, Park Royal, N.W.ro, stating yourrequirements as to output on the D.C. side.No other components should be necessary,but we do not advise you to attempt makinga rectifier of this type yourself, as it callsfor great experience and many special pro-cesses.

Transforming 1)!C. to A.C.T WISH to obtain a small supply of

A.C.5o at 12 volts, either direct or bytransformer. The job does not justifythe expense of a convertor, even if suchcould be obtained, but I believe it ispossible to add slip -rings to a D.C.dynamo or motor which would then runin a similar manner.

Could you give me some informationon the subject such as (a) What machinewould be suitable to produce, say, zoo/24oor 12 volts at 3o/4o watts (50,..) ?(b) The manner in which the alterationshould be made ? My supply is 230 D.C.-R. Seawarden (Weston -super -Mare).THE normal method of changing your

direct current supply to alternatingcurrent of a different voltage is by the use ofa rotary converter, consisting of a D.C.motor running at 3,000 r.p.m. if with 2 -polefields, or at 1,50o r.p.m. if with 4 -pole fields,in order to obtain the desired frequency of5o cycles per second. This motor would bedirect coupled to an A.C. generator having aseparate armature suitably wound for thelow voltage, its field being excited from theD.C. supply with variable resistance in series,so that the voltage can be controlled byvarying the field strength without any changeof speed and frequency. If this is too compli-cated for the present requirements where anoutput of only 3o to 4o volt-amperes arerequired, another method would be to instal aD.C. 230 -volt motor of about 1/6 h.p. and fitthe shaft extension with a pair of insulatedslip -rings. Connections to these rings wouldbe made from opposite points of the motorcommutator (if a 2 -pole field), and an alternat-ing current can then be picked up from theslip -rings by an extra pair of brushes. Onthe slip -rings the alternating current availablewill be about 6o per cent. of the motor inputvoltage, so that if lower voltage is required itwould still require a step-down static trans-former to give the conversion.

Chromium PlatingIHAVE recently installed a small

chromium -plating vat (2-3 gallonscapacity), and I was wondering if youcould help me with the two followingproblems :- '

(r) What is the best method of con-structing an immersion heater to heatthe vat up to 45 deg. C., which wouldwork from the 230 -volt mains ? Thecasing, of course, has to withstand theaction of chromic acid.

(2) Is there a bright chrome bath thatworks at about zo deg. C., current density30-40 amps. sq.ft., using chromic andsulphuric acids ? I have a quantity ofchromic acid of known sulphate content(tohauhn)that could be used. -R. W. Poole

THE difficulty with an immersion heaterwould be to provide it with a casing

that would stand the action of chromic acidwithout deteriorating or causing chemicalaction on the contents of the bath. Youwould probably do better to procure a 500 -watt domestic " hot plate," and stand thevat on this bodily, increasing the size of thehot plate or adding others until the desiredtemperature is obtained. As regards thesecond part of your enquiry, we thinkMessrs. Canning & Co., Ltd., of 133-137,Great Hampton Street, Birmingham, will beable to assist you, as they specialise inchromium -plating equipment.

Ultra -violet Ray LampT SHALL be obliged if you could tell me

whether or not a Siemens (gas -filled)Sieray mercury vapour dual type lightingbulb, 230 volts, 500 watts, gives off ultra-violet rays ?

Will you kindly inform me of a fewsimple tests for ultra -violet rays, alsowhether the above type of lamp wouldbe suitable for sun -ray treatment ?-H. R. J. Dowson (Coln).THE type of lamp which you name definitely

gives off ultra -violet rays, althoughthese rays are mixed with the visible greenishrays characteristic of the mercury spectrum.In order to obtain pure ultra -violet rays fromthe lamp it would be necessary for you topass them through a suitable screen whichwould filter out all but the ultra -violet rays.For sun -ray treatment, however, this is notnecessary.

A good test which you can make to ascertainthe presence of ultra -violet rays is to smear alittle vaseline or petroleum jelly over a sheetof paper or card, and, after holding a sheet ofblue glass in the path of the rays, to bring thiscard in contact with the rays which havepassed through the blue glass. The presenceof ultra -violet rays will at once be indicatedby the. brilliant yellowish -green fluorescenceof the vaselined surface.

Many dyestuffs, such as fluorescence,cosine and acridine yellow fluoresce stronglyunder ultra -violet radiation.

If you employ the lamp specified for sun-ray treatment, you must, of course, provideyourself with goggles of dark blue glass, sincethe rays are very harmful to the eyes.

Sawing Floorboards : A CorrectionIn the article entitled " Odd Jobs in Home

and Garden," in the October issue, an illus-tration is given, showing a floorboard beingcut through with a hand saw.- The boardis wedged up by a piece of wood on the right-hand side of the saw. This is incorrect, as thepiece of wood should obviously be on theleft-hand side of the saw to prevent thelatter seizing when the board is partiallycut through.


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SIR WE. BURNETT & CO. (CHEMICALS) LTD.Ct. West Rd., Isleworth, Middx. Hounslow 0476

CAN YOU PLAY THE PIANOIf you are a music lover, whyhave you not acquired this en-joyable accomplishment andgreat social asset Y Doubtlessbecause the prospect of prac-tice! pract ire! practice! hasdismayed and discouraged you.I have enrolled more than

7.300 adult pupils during the War.During 38 years I have taught over56,000 by post in it third the time,with a quarter the work. at a tenth therxrperise of the ordinary methods ofdull, mechanical wearisome practice,AND I CAN TEACH YOU, Ordinarymusical notation only need. no freak-ish methodn, enabling you to read andplay at sight any standard musical

comPOsition. Send for FREEBook. Say Moderate,Elementary or neu'norr.

Ms. H. BECKER, (Dept. 258) 69. Fleet St., E.C.4

ESPERANTOASIMPLE auxiliary language, easy

to learn and used throughout theworld. To the reader it offersattractive books, both writtenoriginally in Esperanto and trans-lated from other languages. To thestay-at-home it enables pen -friendsto be made in all parts of the world.To the traveller it provides easycontact with people of other lands.Esperanto paves the way to inter-national friendship.A, complete correspondence course,including text book and correctionof exercises, costs only Ss.Write to -day for full particulars, (rec.The British Esperanto Association,Inc., Dept. P169, Heronsgate,

Rickmansworth, Herts.

LARGE DEPT. FOR TECHNICAL BOOKS

FOYLES*BOOKSELLER:, TO THE WORLD *New and secondhand Books onEngineering and other subjects.

119-125, Charing Cross Rd., W.C.2Open 9 a.m.-6 p.m., including SaturdayTelephone : Gerrard 5660 (16 lines)

W. & .

BUY, EXCHANGE OR SELLAdvertisements are accepted for these columns at 5d. per word (minimum 12words at 5s. -advertisements of less than 12 words are charged at the minimumrate of 5s.). TERMS :-Cash with order. Cheques, Postal Orders, etc., shouldbe made payable to George Newnes, Ltd. The Proprietors reserve the right to refuseor withdraw advertisements at their discretion. All advertisements must be received onor before the 5th of the month preceding date of publication and should beaddressed to the Advertisement Director, " Practical Mechanics," George

Newnes, Ltd., Tower House, Southampton Street, Strand, W.C.2.

TOOLS WATCHMAKINGNEW MACHINERY. For Government

Work only. Electric Motors, Band Saws,Drilling Machines, Primps, Grinders.Welders, etc. -John P. Steel, Bingley.

SCALE BUILDING PAPERSFOR ALL LINESIDE STRUCTURES.Gauge (al or Gauge 0. state whii required. sheetof General Railway Station Notices. 8d. Sheet ofDoors, Window., 64. Slate Root Sheet. ConcreteBlocks. New Brickwork. Window Paper (Black orSilver). Red Tiles. English Bond Brick. YellowRubble. Old Stonework. Smoky Bricks -orb.Red Freestone. Bovril Adverts. (20 different).3d. per sheet. POSTAGE 1-11 Sheets lid. extra.

12-18 Sheets 3d. extra.WANTED USED RAIL WA Y MODELS

AND PARTS. PROMPT CASE,

TYLDESLEY & HOLBROOK,109, Deatugate, Manchester 3

COPPER INSTRUMENT WIRE28 S.W.G. Double Silk Covered 7)6 per Its.30 S.W.G. Bnatue1171 and D.C.C. 8/11 per lb.Few other sizes In stock.We also have Buzzers 5/6, 5 -watt Lamps 2;4." PhiLidspe."Cycle Dynamo Sets 363- and 92/6. FlexibleCords, etc.Alt prices plus postage. Leaflets of goods availablesent on receipt of stamped addressed envelope.L. WILKINSON, 204, Lower Addiseombe Road,

Croydon.

WATCH AND CLOCK REPAIRERS.Send 9d. for complete list of materialsand tools.-Blakiston & Co., Ainsdale,Southport.

MISCELLANEOUS

FIRM engaged in Light Engineeringwish to contact inventors desiring tocommercialise their inventions. -Box 137,c/o " Practical Mechanics," Tower House.Southampton Street, Strand, London,W.C.2.

WANTED

SHOP MANAGER required by lightengineering firm. 100 employees. Onlythoroughly practical men need apply,Cotswold area. Salary .18 per week, plusbonus. Good prospects. -Box 138, c/o" Practical Mechanics," Tower House,Southampton Street, Strand, London,W.C.2.

ANY Trix, Dublo or Marklin 00 railwaypurchased. Every offer acknowledged.-Box 139, c/o " Practical Mechanics,"Tower House, Southampton Street, Strand,London, W.C.2.

WANTED.-Aero engine, about 6 c.c.Prefer raby Cyclone. -G. Moorby, 54,Beeby Road, Grimsby.

BOLT DOWN THAT MACHINE IN HALF THE _TIME

with CINCH Bolt AnchorsSuitable for all fixings to walls, ceilingsand floors of cement, brick, stone, etc.

No delay : full load can be appliedimmediately. Depth of hole

40% to 60% less than ordin-ary fixing methods. Cinchanchors give a quick andpositive bite that holds per-

manently. Will not slacken orwork loose. Sizes to suit all

IMMEDIATE DELIVERY.

Free. SEND FOR DETAILS AND SAMPLE ANCHOR and prove our claims

HOYT METAL CO. OF GT. BRITAIN, Dept. G, Deodar Rd., Putney, London, S.W.15

JUBILEE HOSE

longL-IIPifeS

clip with theever -tight

gripThe Best Known

ForRadiator Joints,Air, Oil andWater Hose

JointsWe guarantee a

Tight JointL. ROBINSON & Co

25, LondonChambers.

GILLINGHANLKENT

ELECTRIC ETCHIN6 EQUIPMENT

AS SIMPLE TOUSE AS A PENWill etch on anymetal. Quicker than,machine engraving.from Dealers or direct.

.call -t ztx..

LI I

(MINISTRYSPECIAL OFFER

A Sample Parcel ContainingMany Useful Pieces of

CHEMICAL APPARATUS

3/6 free)iposi

A WIDE RANGE OFEQUIPMENT AND REAGENTS

for Experiments at Home canbe chosen fr6m our Catalogue-write for free copy, enclosingstamped (Id.) addressed

envelope.BECK(Scientific Dept. A), 60 High St.,

Stoke Newington, London, N.16

This space will be used to advertisethe 'ADEPT' LATHES andSHAPERS in the happier timescoming, when we hope to be able togive more prompt deliveries. Mean-time we would assure all our friendsthat we are making strenuous en-deavours to give deliveries of theorders we have on hand and asktheir kind indulgence.

ELECTRADIXBARGAINS

9l6 RHEOSTATS to 1 ohm and off. Carries 4 amps.1.ef for any cprrent regulation sub -circuit batterycharge, or for dimming on 6 to 12 volts. One -holefixing with plated bracket for table or rack. Trans-lucent pull -off knob has bulb socket. U.S.A. make.New, in carton, 2/8. Well worth 5/,MAGNETS. The Wonder Midget 0 -oz. Permanent

Magnet. Discs of Mni Steel. Tremendousmagnetic force and only 1.3/16in. dia. x tin. thick,with soft centre for drilling. One leaps off the tableto meet another. Uses , Any magnetic duty, metalseparation, magnetic chucks and lifters. Cut-outcore, polarises, solenoid sores, headphone re-wag-netiners. etc., 213 each, or 4,6 pair. A.C./D.C.Mains Magnets, 2 wound poi., 110 or 220 volts, 71b.lift. 5 6. Small 12 -volt solenoids, tin- x lin.plunger. 86.ELECTRIC Miniature 12 volts Autopulse Pumps,

metal diaphragm. with filter. Suction anddelivery, totally enclosed for spirit, petrol or water,

HONE GUARD Handeombs. Micro -telephones orTransceivers for field telephones. Govt. all -

metal type No. 16, with centre linger switch, 15/-.4 -way Cords, 2/6 extra. There are a number withcentre switch damaged-ln transit, no cords, saleprior, 7/8.

BUZZERS, etc. A.C. Mains Buzzers for 0 volts,4/, A.C. Donee Bell. 6 to 8 volts. 211n. gong,

44. Combination A.C. Bell and Mal. Transformer,10(6. Practice Burger, bakelite ease, 2/-, Squarebrass care, 4,1. Heavy Type, bakelite case, 5/8.D111 double core m ul ti-wonnil Buzzers, less contacts,5/6. The famous Tiny Townsend Buzzer, 10/-.

PERISCOPES.Trench type, opens 25in. high

41in. x sip., with spare mirror, folding intocanvas carrying case and sling, 12/8, poet 11-.nitY CELLS, If volt. for Telephones and Fieldan, Sets, Siemens Type 3 x 2, or S Dn. x.11in. xqin., 2;6, plus tea 11(4.SOLO VARIABLE AIR CONDENSERS for

Wavemeters and single Ciretflt Tuning,logarithmic blades, .0005 mfd., new. Type F..boxed, 4/6. Condensers. Fixed, 2 tad. G.P.O.for smoothing, 2,6. H.T. Mica Fixed -Condensers,1-9 natl., 9,000 volts, 10/, Lange 1 mid., 2,000 volts,10!8. 1 mfd., 0,000 volt., oil -tilled 111 condensers,35', 2 mfd., 4,000 volts, ailed, 45/-.MULTI -SWITCH 8 -way hoses. Lucas change -over

and fuses, 3/6. 6 -way push-button Switches,R.A.F. itero 2/9. Rotary Switches, R.I. 7 stud,box base, 7,8.CHIJCIL JAWS, New. 100 sets of :3 -jaw self -

centring Cushman type scroll. Three sires,21in. set of 3 jaws, 8/- ; Do. jaws, 8/- set. Size gin.jaws, 10/-, set of three.ELECTRIC SOLDERING IRONS, 00 watts. Copier

hits and beaters replaceable, 1216.

DRILLS. Electric Bench Drills, D.C. Wolf, 110volts, massive pillar type, geared feed, counter

weight nine, No. 1 mores socket for pin. steel. Gmbe unshipped for portadde sue. 12 for deliverywithout permit, each.

DYNAMO BARGAINS. Rotas, 412 volts, 8 amps.,D.C., Jul brush site, Sin. x 911n., 11 lb., cost

610, unused, 17/6 carriage paid England and Wales.G.E.C. Double -current Dynamos, 6 volts and 000volts, ball -bearings, 17th., as new, 27/8, carriagepaid England and Wales. Charging Dynamos,

colts, 15 amps., Crompton, 3,000 revs., 26/10/-.

ENGINESfor direct coupling: twin cyl. Douglas

fan -cooled, It h.p., governed, nag. 'ignition,light weight,* 212. Larger, 21 h.p. ditto, 815.12 -volt Petrol -Electric Lighting Set, second-hand,Sr mot type, with two 6 -volt batteries, 215. 50 -volt,

I,W. Sets, water cooled. 225.VULTOGRAMI. Chart Dunn and Clips, 5/6.

Magnetic Clutch. 6 veils. complete, 25/...,. Traverse Shaft, tin. threaded 120 to inch. with

hearings, 12/6. Stylus. with carriage rods andbrackets. 7/8. 5 -pin pings. with panel socket andcoral, midget type, 41 pale. 14 -way Plug andSocket, with cord. 74. Radio 2 -pin Midget BellingPlug and Socket, 94. Plugs only. 5!- doz. 1 -pairsof sockets on panel, 2/-. kin. Aluminium Panel,drilled 13in. 0 Olin. 3/-. Bakelite ditto, 71in. xs Ns., 2/3.A C. SLOT HOUSEKETERS for Shillings, newra chamberlain .0 halo. 10 amps., for fuelonttolling-

(ZONIZER3.For air purification. Small wall

onedube type for A.C. Mains, endorsed inw bite enameled rase, 21/..

Pletve add postage fo, all mailorders. Send stomped envelope

for 1-ep,iea to all enquiries.

ELECTRADIXRADIOS

1), Broughton Street, Battersea,London, S.W.8.

Teleph,ne :Vacant a, 2130

Rallwx EtatRin. Queen's Road, Battersea, fromWaterloo.

Easily Madefrom our cast-ings, from15/- per SetJ. HALLAM

& SON,Upton, Poole,

Dorset.MINIATURE PETROL ENGINES for

Aeroplanes and Speed Boats.2send 3e1. f.,r articular&


30191 tziLe, 0:asida - "Success in Sngiortzvaiiv" 410

One of the following Courses taken at home in yourspare time can definitely be the means of securingsubstantial promotion in your present calling, or entryinto a more congenial career with better prospects.

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Men and Youths urgently wanted for reservedoccupations as Draughtsmen, Inspectors, etc.,in Aero, Jig and Tool, Press Tool, Electrical,Mechanical and other Branches of Engineering.Practical experience is unnecessary for thosewho are willing to learn-our Guaranteed

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148, HOLBORN, LONDON, E.C.I

FIFTY-SEVEN YEARS OFCONTINUOUS SUCCESS

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We.recommend all readers interested in improving their positionto apply -for a copyof this valuable book. " Suc'eess inEngineering" is not a pamphlet. It is a 124 -page book, con-thining 'valuable and vital information on all branches ofengineering .There are many engaged in engineering whoowe their success to The 'National Institute of Engineering.The FREE GUIDE explains :

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Write now for yourcopy of this remarkablepublication.A.M.I.E.E., A.M.I.Mech.E.,A.M.Brit.I.R.E., A.M.I.P.E.,A.M.I.C.E., A.M.I.Struct.E.,A.M.I.A.E., A.F.R.Ae.S.,A. M. I .S. E M.R.San.I.,London B.Sc., Degrees.Fully guaranteed postal courses forall the above and many otherexaminations. Fully described inthe Free Guide.

THE ACID TEST OF TUTORIAL EFFICIENCYSUCCESS-OR NO FEE

We definitely guarantee that if you fail to pass the examination forwhich you are preparing under our guidance, or if you are notsatisfied in every way with our tutorial service-then your TuitionFee will be returned in full and without question. This is surelythe acid test of tutorial efficiency.

If you have ambition you must investigate the Tutorialand Employment services we are able to offer. Foundedin 1885, our success record is unapproachable.

Why not fill in and post the attached coupon NOW for further detailsand Free Authoritative Guide (free while present stocks last)to openings in Engineering and Building ? This book contains amine of valuable and exclusive information and may well prove tobe the turning point in your career.

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To NATIONAL INSTITUTE OF ENGINEERING/ (Dept. 29), 148, Holborn, London, E.C.1.Please forward your FREE Guide to :

NAME

ADDRESS

FREE COUPON

My general interest is in : (i) ENGINEERING (Place rims? against

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To be filled en where you already have a special preference.FOUNDED 1885 - - - OVER 100,000 SUCCESSES

"Practical Mechanics" Advice Bureau COUPONThis coupon is available until November 30th, 1042. andmust be attached to all letters containing queries, togetherwith 3 penny stumps. A stamped, admired envelope

roust also be enclosed.Practical Mechasirs. November, 1942.

Published about the 30th of each month by GEORGE NEWNES, LIMITED, Tower House, Southampton Street, Strand, London, W.C.2. and PrintedIn England by The New.° and Pearson Printing Co., Ltd., Exmoor Street, London. W.I0. Sole Agents for Australia and New Zealand-Gordon & (iotch,Ltd. Sole agents for South Atrica--Ceutral News Agency, Ltd. Subscription Rates : Inland 11s. per annum. Abroad, 10e. 6d. per annum. Canada, 100.

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THE HOTSPUR GLIDER - WorldRadioHistory.Com · 2019. 10. 23. · Noverrfber, 1942 NEWNES PRACTICAL MECHANICS 37 Modern Workshop PracticeE PULL S By F. JOHNSTONE TAYLOR 780 PAGES 542