966 SEIZURE AND CONDEMNATION OF TUBERCULOUS MEAT.

high vacua. Indeed, by plunging charcoal into liquidhydrogen the vacuum obtained owing to condensation of thehydrogen within the pores of the charcoal became so highthat no electric discharge will pass. In a similar experi-ment in which helium was substituted for hydrogen thevacuum was so high that a coil giving a four centimetrespark in air had to be used before a phosphorescent dischargecould be obtained, and then the spectrum shown was due toglass. Carbon clearly, therefore, has a marked selectiveaction for helium and the experiment suggests that thiselement may prove to be a valuable "finder" of heliumin gases, and possibly of other gases not yet known to us.It is not a little curious that this occluding property ofcarbon which has been known for a very long time has notbeen tried before in the search after rare gases. Even coke

occludes gases in surprisingly large quantities and furthershows a selective action in this respect. Thus coke will

completely absorb the oxygen from the air, leaving purenitrogen, a residue of nitrogen, however, being found in theporous substance but no oxygen. It is probable that in thiscase, therefore, the oxygen has combined with the hydrogenof the coke to form water as there was no evidence of anycarbon being oxidised. Further experiments with the

occluding property of charcoal in connexion with the questafter new gaseous elements and the determination of the

properties of those already discovered will be looked forwardto with considerable interest.

SEIZURE AND CONDEMNATION OF TUBER-CULOUS MEAT.

IN the report of the Select Committee of the House ofCommons on the Tuberculosis (Animals) Compensation Bill,1904, reference was made (a) to the variety of practice allegedto exist with regard to the amount of tuberculous depositthe existence of which in a carcass is held to justify its totalcondemnation ; and (b) to complaints made by butchers asto the injury caused to them by their prosecution in opencourt for having tuberculous meat upon their premises. A

circular has been issued by the Local Government Boarddrawing attention to these two points and making sugges-tions as to the course which should be pursued by the meatinspectors. The members of the Royal Commission (1898)were of opinion that the entire carcass and all the organs of ananimal should be seized under the following conditions: (a)when there is miliary tuberculosis of both lungs ; (b) whentuberculous lesions are present in the pleura and peri-toneum ; (e) when tuberculous lesions are present in the

muscular system or in the lymphatic glands imbedded in orbetween the muscles ; and (d) when tuberculous lesions existin any part of an emaciated carcass. The Commissionfurther suggested that the carcass if otherwise healthy shouldnot be condemned but every part of it containingtuberculous lesions should be seized (a) when the lesionsare confined to the lungs and the thoracic lymphaticglands ; (b) when the lesions are confined to the liver;(e) when the lesions are confined to the pharyngeallymphatic glands; and (d) when the lesions are confined toany combination of the foregoing but are collectively smallin extent. The Local Government Board, after a full con-sideration of these recommendations, came to the conclusionthat measures more stringent than those advocated by theRoyal Commission are not called for. This decision is a

perfectly right one, especially as the subject of bovine tuber-culosis is at present being investigated by another Com.mission. The Board has, however, acted wisely in insistingupon the expediency and desirability of compelling thoseofficers who are employed as meat inspectors to act in directaccordance with the principles thus laid down if any slacknessin this respect exists. With regard to the prosecution ofbutchers the Select Committee expresses the view that if a

butcher who is in possession of tuberculous meat has notified’the fact to the proper authority as soon as he could be reason-ably expected to be aware of it the case should not be taken

into court. This decision is also a wise and just one, forserious consequences may result to the business of a butcher-

from prosecution in open court for being in possession oftuberculous meat. If, however, such possession is volun-tarily and promptly disclosed by the owner the carcass or-

its parts can be destroyed and so the necessary protection tothe public can be satisfactorily assured without any furtherlegal proceedings. -

THE first meeting of the forty-ninth session of the WestKent Medico-Chirurgical Society will be held at the RoyalKent Dispensary, Greenwich-road, S.E., at 8.45 P.M., on

Friday, Oct. 7th. The President, Dr. Robert E. Scholefield,will occupy the chair. After the formal business a clinical

evening will be held, when cases and apparatus will beshown by Dr. F. S. Toogood, Dr. M. Dockrell, Dr. L. L. B.Williams, and Dr. G. Herschell.

THE opening meeting of the twenty-third session of the-West London Medico-Chirurgical Society will be held at theWest London Hospital on Friday, Oct. 7th, at 8.30 P.M.The presidential address will be delivered by Mr. C. M.

Tuke, the subject being " Progress in Psychology."

THE annual dinner of the Association of Public Vaccinators.of England and Wales will be held at the Hotel Cecil,Strand, London, W.C., on Friday, Oct. 28th, at 7 P.M. Allcommunications should be addressed to Mr. Charles Green,

wood, 1, Mitre-court-buildings, Temple, E.C.

IT is announced that the boatswain of the Londonsteamer Bishopsgate, now at Jarrow-on-Tyne, is sufferingfrom plague and has been removed to the floating hospitalfor infectious diseases. The Bishopsgate has come fromRosario, South America, calling at Hamburg.

WE regret to announce that Professor Finsen of

Copenhagen died on Sept. 25th in his forty-third year.It will be remembered that the Nobel prize was awardedto him about a year ago. We hope to publish an obituarynotice at an early date. -

A MEETING of the East London Medical Society will beheld on Tuesday, Oct. 4th, at 3.30 P.M., in King’s AssemblyRooms, Cottage-grove, Mile End-road, near Burdett-

road, E.

AT St. Thomas’s Hospital Medical School theentrance scholarship in natural science, of the valueof .6150, has been awarded to Mr. Ernest WilliamWitney, and the University scholarship, of the value of 50,to Mr. Charles Ernest Whitehead, B.A., of Caius College,Cambridge.

HEALTH OF DEVONPORT.-The medical officerof health of Devonport (Mr. J. May) in his annual reportfor 1903, which has just been issued, states that during theyear the births numbered 2055, giving a birth-rate of23’ per 1000. The number of deaths was 1055, equal toa death-rate of 14’ 2 per 1000. The average birth-rate anddeath-rate for the preceding 10 years were 26’ 8 and 16 per 100!}respectively. Mr. May adds that hitherto all the sewagehas been allowed to flow untreated into the river Hamoaze.This is now prohibited by the Admiralty and the drainageof the suburbs of Devonport will have to be treated speciallyso that none but a clear effluent shall be discharged intothe Hamoaze.

967THE EVOLUTION OF MAN’S DIET.

THE EVOLUTION OF MAN’S DIET.

BY HARRY CAMPBELL, M.D., F.R.C.P. LOND.,PHYSICIAN TO THE NORTH-WEST LONDON HOSPITAL AND TO THE HOS-

PITAL FOR NERVOUS DISEASES, WELBECK-STREET.

IV.l

HAVING now completed our general survey of the variousdiet epochs we may proceed to treat of each in detail.

THE ANTHROPOID PERIOD.

The anthropoid period began with our generalisedanthropoid precursor, as represented by some such beingas the extinct dryopithecus with a cranial capacity of 3

or under, and it continued till the appearance of that

anthropoid precursor which stood at the same level as

the present-day great apes now stand, with a cranial

capacity of 5, or somewhat less. The food of our anthro-

poid precursors was probably much the same as that

of the existing anthropoids, and in order to ascertain whatit was we must therefore inquire into the diet of the apes.We may also gain some help in this direction by studyingthe diet of the remaining primates, or " monkeys," as someterm them, in contradistinction to the " great apes." Butbefore entering on this inquiry let us consider the factorswhich determine the food of animal species.Factors determining the food of animal species.-1Ne find

these to be three in number : 1. The kind of food available-i.e., the nature of the flora and fauna where the speciesis located. 2. The desire or prompting for certain foods;while this varies with every species it will be foundthat all animals in their choice of foods are influenced,consciously or unconsciously, by three considerations: thedegree of concentration of the food, its digestibility, and itstaste, the tendency of every animal being to seek out food inas concentrated, digestible, and palatable a form as possible;a concentrated and easily digestible food has the greatadvantage that it can be procured and assimilated with theminimum expenditure of energy. Of vegetable foods seedsand roots are the most concentrated, but of all natural foodsanimal tissue is at once the most easily digested and themost concentrated, and given the necessary facilities evenherbivorous species tend to become carnivorous, while thereverse, so far as I know, never occurs. In winter thereindeer eats flesh and in seasons of dearth farmers havebeen known to feed their cattle and even their horses on

fish, but the carnivora cannot digest vegetable food unlessit is artificially prepared. All the carnivorous mammalswere originally vegetable feeders. In regard to the palatable-ness of any given food this, of course, varies with differentspecies ; what may be highly palatable to one may excitedisgust in another ; there may be species which revel inbitter and sour foods such as aloes and sloes but probably the I

tendency of all the mammals, certainly of the higher ones,is to avoid bitter and sour-tasting foods in favour of thosethat are sweet or possessed of delicate flavours. Withinlimits sourness is tolerated even by man who’sometimesmanifests an actual craving for sour things, such as lemons.One of the chimpanzees at the London Zoological Gardensis very partial to this fruit and there can be little doubtthat in their natural state the anthropoids subsist

largely on bitter and acrid substances from which thehuman palate would recoil in disgust. Nevertheless,the tendency is probably in the direction indicated.3. The degree to which the skill needful to procurethe desired food is possessed by the species. Obviouslythe greater the intelligence and the better the physicalequipment needful for securing a food-e.g., that neededfor climbing a tree or grasping an object-the more success-ful is the animal likely to be in obtaining it. Among therodents the stupid rabbit, unable to climb and with littleprehensile power, has to be content with a bulky diet ofcomparatively innutritious herbs, while the more intelligentsquirrel, a nimble climber and possessed of considerableprehensile power, is able to procure highly nutritious seedsand not a little animal food. The intelligence and nimble-ness of rats, again, enable them to procure highly con-centrated and palatable foods; they haunt the abodes of

1 Nos. I., II., and III. were published in THE LANCET of Sept. 10th,(p. 781), 17th (p. 848), and 24th (p. 909), 1904, respectively.

man and pillage the food, animal as well as vegetable, whichhe has stored for his own use.

All changes which the diet of our ancestors has

undergone since pre-anthropoid times are to be explainedby reference to these three factors. We shall see

that the food of the great apes and the monkeysis for the most part concentrated, consisting of the moreconcentrated vegetable foods and of that most concentratedof all food-animal tissue. The facts that many of the

monkeys are provided with a large csecum and that all thegreat apes possess a vermiform appendix, indicating theirdescent from ancestors possessing a very capacious csecum,show that both the apes and the monkeys are derivedfrom beings whose diet was more bulky than is their own.Evidently with the advance in intelligence and dexteritythe evolving primate gradually abandoned a herbivorous forthe more concentrated frugivorous diet, becoming alsoan animal feeder. That monkeys and apes, in spite of theirgreat intelligence, are not more carnivorous than they are isprobably to be explained by the facts that they are essentiallyarboreal in their habits and are not endowed with the

necessary physical equipments for securing an abundance ofanimal food. I have already insisted that it was not until ourancestors had learnt to fashion weapons and traps that theywere enabled to secure a plentiful supply of animal food.Coming now to the food of the primates it is to be

observed that zoologists include under this order the lemur-like animals (Lemuroidea) and the man-like animals (Anthro-poidea).2 The true lemurs are by some not included amongthe primates, being termed by the Germans half-monkeysand by the French false monkeys ; they show affinities tothe insectivora. The anthropoidea include among othersman, the great apes (gorilla, chimpanzee, orang, gibbon),the baboons, and-lowest branch of all-the marmosets,further below the great apes than the latter are belowman. The reaction of the blood of the various membersof this group affords, as E. H. F. Nuttall has so ablyshown, a valuable means of determining their relative eaffinities to man.3 This method of testing shows that thegreat apes are the most closely allied to man ; that the groupwhich includes the baboons comes next, while the lemuroidsgive no indication of blood relationship.DIET OF THE MONKEYS (PRIMATES BELOW THE GREAT...

APES). ... , .

The lemurs proper eat fruits, birds’ eggs, birds, mice, andinsects, and one species is said to eat honey.The lemnr-like animals eat fruit, leaves, birds’ eggs, small

birds, reptiles, and insects. One of the best known of thesecreatures is the aye-aye, a native of Madagascar. Its foodconsists largely of the larvse of a beetle ; it drinks after themanner of many monkeys-by dipping the fingers into thewater and drawing them through the mouth ; it is said bysome to eat honey.

-31-armosets, the lowest anthropoids and the most nearlyallied to the lemuroids, subsist on insects and fruits, not

disdaining flesh, including fish.Baboons (11 species) are omnivorous. Their food consists

principally of insects, which they search for under stones,turning the latter over with their hands, larvae of beetles,caterpillars, lizards, eggs, nestlings, mice, fruits, and roots;in South Africa they will rip open lambs to get the milkout of the stomach and will pelt an enemy with stones. The

Doquera baboon goes about in large herds ; these animalshunt their prey, chiefly small ruminants, like a pack ofhounds, following the quarry till it is exhausted. Thechacma, the largest of all the baboons, subsists on scorpions,centipedes, and all manner of insects, birds’ eggs, gum andhoney, and the bulbous roots of certain liliaceous plants,in the procuring of which it often displays considerableingenuity. Le Vaillant’s pet chacma would lay hold of atuft of leaves with its teeth and pressing its four pawsfirmly against the earth and drawing its head backwards theroot generally followed; when this did not succeed itseized the tuft as before as close to the earth as it could,then throwing its heels over its head the root yielded to thejerk it gave it. The Anubis baboon digs up the roots ofgrasses. The Arabian baboon lives chiefly on insects andsuch creatures as it finds under stones or among rocky cliffsand ravines. The Gelada baboons are known to roll down

2 It should be noted that the term "anthropoid" is by many con-fined to " the great apes," and it is in this sense that I have used it inthese papers.

3 Blood Immunity and Blood Relationships, &c.