The MARYLAND SURVEYOR - theamericansurveyor.com · The MARYLAND SURVEYOR ... Compensation must be ... solar or star observation to Magnetic North from the compass observation

Newsletter/Journal of the Maryland Society of SurveyorsVolume 30, No. 2 December 2003

President’s Message.......................................... 2From the Desk of the Executive Director ........ 3From the Editor’s Desk..................................... 4M.S.S. Fall Conference at Solomons ................. 52003 Plat Contest Winners ............................... 7The New Retired-Status License ......................... 8Surveyor of the Year......................................... 9Our First Chapter of the Year ......................... 10Ralph Donnelly, Gone But Unforgettable ....... 12Susquehanna Chapter Golf Tournament ........ 14Mr. Ripley Heads South. . . ............................. 17What Happened at ACSM? .............................. 18Dottie Sutcliffe—1922-2003 ........................... 21The Compass Meridian Stones of Frederick ... 31

IN THIS ISSUE

The MARYLANDSURVEYOR

DOTTIE SUTCLIFFE, 1922-2003

“STARGAZERS”OF M.S.S.

For five generations, two strangebut very special stone monuments havegraced Old Courthouse Square Old Courthouse Square Old Courthouse Square Old Courthouse Square Old Courthouse Square inFrederick. Not boundary markers,although often mistaken for such, theyare actually Compass Meridian Stones,Compass Meridian Stones,Compass Meridian Stones,Compass Meridian Stones,Compass Meridian Stones,mandated by the Maryland Legislature in1870 for the purpose of calibratingsurveyor’s compasses to magneticdeclination.

Since 18961896189618961896 the two stones havestood, perfectly aligned with True NorthTrue NorthTrue NorthTrue NorthTrue North,waiting to help the surveyors of centralMaryland adjust their compasses — untila few years ago, when a TV camera truckknocked monument “South Magnetic”“South Magnetic”“South Magnetic”“South Magnetic”“South Magnetic”out of position.

As a volunteer project on October 11th, “stargazers” from M.S.S. Appalachian ChapterM.S.S. Appalachian ChapterM.S.S. Appalachian ChapterM.S.S. Appalachian ChapterM.S.S. Appalachian Chapter used Ralph Donnelly’s Ralph Donnelly’s Ralph Donnelly’s Ralph Donnelly’s Ralph Donnelly’s portableMason-Dixon Mason-Dixon Mason-Dixon Mason-Dixon Mason-Dixon Observatory Hut for its actual original intended purpose — not as an interesting historical display, but to shootPolaris, Polaris, Polaris, Polaris, Polaris, like Days of Olde, and reset the Compass Meridian Stones of Fredericktowne.Compass Meridian Stones of Fredericktowne.Compass Meridian Stones of Fredericktowne.Compass Meridian Stones of Fredericktowne.Compass Meridian Stones of Fredericktowne. Page 28.

Our Maryland Society ofSurveyors has been blessed acrossthe years by countless fine peoplewho volunteered their time andtalents to help — but none didmore ever than good Draper Draper Draper Draper Draper andDottie Sutcliffe.Dottie Sutcliffe.Dottie Sutcliffe.Dottie Sutcliffe.Dottie Sutcliffe. To their skilledand devoted hard work,completely unpaid in the ‘60sand ‘70s, this organization owesits very existence today. Draper,Draper,Draper,Draper,Draper,at our recent SolomonsConference, was honored withthe Society’s Russ LowmanRuss LowmanRuss LowmanRuss LowmanRuss LowmanAwardAwardAwardAwardAward — highly deserved — butfor the first time in memory, goodDottie Dottie Dottie Dottie Dottie wasn’t there. She passedaway October 7. Appreciationon Page 21.

Knocking in the last wooden roof peg, Matt BrienMatt BrienMatt BrienMatt BrienMatt Brien of the Appalachian Chapterprepares Ralph Donnelly’sRalph Donnelly’sRalph Donnelly’sRalph Donnelly’sRalph Donnelly’s replica Mason-Dixon ObservatoryMason-Dixon ObservatoryMason-Dixon ObservatoryMason-Dixon ObservatoryMason-Dixon Observatory for the Chapter to sight

Polaris, October 11 at Frederick.

December 2003 — Page 31

THE MARYLAND SURVEYOR

www.marylandsurveyor.org

INTRODUCTION

“I’m beginning to see a few stars, but which one isPolarisPolarisPolarisPolarisPolaris?” Charles MasonCharles MasonCharles MasonCharles MasonCharles Mason and Jeremiah DixonJeremiah DixonJeremiah DixonJeremiah DixonJeremiah Dixon neverasked that question, but some of the AppalachianChapter surveyors did. After night had fallen on October11 and stars had begun to peek out here and therethrough the cloud cover, the surveyors were stillworried. After all, you can’t observe stars if you can’t see‘em. Waiting there after having erected the portableobservatory (affectionately known as “the Hut”) in BakerPark, a city park near Frederick’s downtown, andwatching the solid cloud cover to the north, they jokednervously. “Let’s sight the South Star instead” and “Nexttime, we’ll put the Hut on wheels!” Chapter ChairmanRob KundrickRob KundrickRob KundrickRob KundrickRob Kundrick, who scheduled the event, remainedunruffled. He was convinced the evening’s activitieswere already a sure success. RobRobRobRobRob had consulted theFarmer’s Almanac.Farmer’s Almanac.Farmer’s Almanac.Farmer’s Almanac.Farmer’s Almanac.

A GLANCE BACK

Two short, very spe-cial, granite pillars haverested in the front lawn ofFrederick’s City Hall, alsoknown as the Old Court-house Square, for a verylong time, patiently wait-ing for someone to grantthem proper recognition.(See The Maryland Sur-veyor, Volume 26, No. 4,July 1999). The CompassMeridian Stones ofFrederick, Maryland wereFrederick County’s re-sponse to the mandate toset Meridian Line Stones asoutlined in the AnnotatedCode of Maryland, 1870,

Article 25, Sections 123-127. United States Coast andUnited States Coast andUnited States Coast andUnited States Coast andUnited States Coast andGeodetic SurveyGeodetic SurveyGeodetic SurveyGeodetic SurveyGeodetic Survey leveling crews included them in a1941 2nd order leveling run and dubbed them “NorthNorthNorthNorthNorthMagneticMagneticMagneticMagneticMagnetic” and “South MagneticSouth MagneticSouth MagneticSouth MagneticSouth Magnetic”.

Realizing their importance during 1998, theAppalachian ChapterAppalachian ChapterAppalachian ChapterAppalachian ChapterAppalachian Chapter began working toward preservingthe Stones, which, because of their Benchmark status,are listed in the National Geodetic SurveyNational Geodetic SurveyNational Geodetic SurveyNational Geodetic SurveyNational Geodetic Survey controlmonumentation database.

PREPARATIONS

The Chapter had several reasons for choosing thisparticular site in Baker Park for their celestialobservation. The marker “Compass Ref,Compass Ref,Compass Ref,Compass Ref,Compass Ref,” as its nameattests, had been placed in 1998 by members of theChapter at an open area in Baker Park to accomodate

transferring an accurateAstronomic North to theCompass Stones for theresetting of “South Mag-South Mag-South Mag-South Mag-South Mag-neticneticneticneticnetic”. Accurate “survey-grade” geographic posi-tions had previously beenestablished for both “Com-Com-Com-Com-Com-pass Refpass Refpass Refpass Refpass Ref” and for “NorthNorthNorthNorthNorthMagneticMagneticMagneticMagneticMagnetic” prior to thisobservation. For two daysduring February 1999, RoyRoyRoyRoyRoyAndersonAndersonAndersonAndersonAnderson of the NationalNationalNationalNationalNationalGeodetic Survey Geodetic Survey Geodetic Survey Geodetic Survey Geodetic Survey and RobRobRobRobRobFarrarFarrarFarrarFarrarFarrar, Surveyor-Par-Excel-lence, had teamed to posi-tion the Stones using first-order GPS equipment andtechniques. “Compass RefCompass RefCompass RefCompass RefCompass Ref”had been included in Year2000 citywide horizontaland vertical control net-work by Frederick City

THE COMPASS MERIDIAN STONES OF FREDERICK, MDINSTALLMENT TWO: OBSERVING POLARIS

October 2003

By: R. Wayne Twigg

The North Magnetic Stone North Magnetic Stone North Magnetic Stone North Magnetic Stone North Magnetic Stone on the Old Courthouse Squareat Frederick City Hall, has stood undisturbed since 1896.

Page 32 — December 2003



Surveyor Bill Lankford. Bill Lankford. Bill Lankford. Bill Lankford. Bill Lankford. Finally, a Grid Azimuth had beenturned to City Hall’s weathervane.

A LONG LOOK BACK

Let’s discuss for a bit some of the conditions thatbrought about the establishment of Frederick’s CompassMeridian Baseline. Survey lines “laid in” with a Compass arefairly difficult to consistently and accurately reproduce witha Compass, due to various and varying factors such as localattraction, mineral deposits, diurnal variation, vernier scalelimitations and the variations of magnetic declination fromone year to the next. Compass scales and verniers must beprecise, needle pivot points must be undamaged and sharp,and vanes true. Inaccuracies of the magnetic bearings oflines can also be increased by divergence. To furthercomplicate matters, Magnetic North is ever-changing.Gravimetric studies have shown that the density of Earth’smass under any given location will change during relativelyshort time periods due to movements of crustal plates. Thisis the major reason that Surveyor’s Compass Needle variesfrom Astronomic (sometimes called “True”) North. Thevariation is called Magnetic Declination and is illustrated bythe wavy lines on an Isogonic Chart. Compensation must bemade for all of these factors, and a few more. Therefore itisn’t difficult to understand how precise and accurate“survey-grade” measurements with a Compass are, inessence, impossible in many settings. Loss of accuracybecomes assured when the Surveyor using the Compassdoesn’t recognize these factors and apply compensationproperly.

All this helps explain why the surveys of two goodprofessionals, Lawrence BrengleLawrence BrengleLawrence BrengleLawrence BrengleLawrence Brengle, elected as the firstMayor of Frederick in 1817, and Thomas WoodrowThomas WoodrowThomas WoodrowThomas WoodrowThomas Woodrow,Frederick County Surveyor at the time, didn’t coincide.Mr. Brengle’sMr. Brengle’sMr. Brengle’sMr. Brengle’sMr. Brengle’s original layout of Frederick Towncontained lines that ranged from 5 to 20 feet off.Concerned with accuracy and looking for the source ofthe difference, they corresponded in 1820. Their lettersdiscuss the results of field tests in which a 12-footmeasuring rod proved to be too long by a quarter of aninch and compass readings that tended to primarily differby as much as 10 minutes of arc from the effect of diurnalvariation on the needle. Their search for excellencehelped to set events in motion that caused FrederickCounty’s Compass Meridian Line to be established.

Currently, the Local Magnetic Declination for theFrederick area is approximately 11°07’ west ofAstronomic North, as shown on the calculation sheetincluded further on in this article. Incidentally, if thesurveyor records the magnetic bearing of a backsight lineand at the same time determines the astronomic bearingof it, then the Local Magnetic Declination can easily bedetermined by comparing Astronomic North from thatsolar or star observation to Magnetic North from thecompass observation.

The investment of time to perform an astronomicobservation to determine Astronomic North is approxi-mately 15 minutes for two good field personnel and 20 to25 minutes for one competent office person. It can evenbe much less if a good software package, such as Elgin,Elgin,Elgin,Elgin,Elgin,Knowles and Senn, Inc.’s Astro*Disk83,Knowles and Senn, Inc.’s Astro*Disk83,Knowles and Senn, Inc.’s Astro*Disk83,Knowles and Senn, Inc.’s Astro*Disk83,Knowles and Senn, Inc.’s Astro*Disk83, is used. EKSIEKSIEKSIEKSIEKSI

The South Magnetic StoneSouth Magnetic StoneSouth Magnetic StoneSouth Magnetic StoneSouth Magnetic Stone, which was disturbed andmust be reset.

The monument “Compass Ref.” on the grounds at BakerPark in Frederick.




provided the excellent data, instructions and charts usedby Chapter Surveyors for this observation. The booklet ispublished each year as Sokkia’s Celestial ObservationCelestial ObservationCelestial ObservationCelestial ObservationCelestial ObservationHandbook and Ephemeris.Handbook and Ephemeris.Handbook and Ephemeris.Handbook and Ephemeris.Handbook and Ephemeris.

The amount of personnel time is essentially the samewhether for a sun shot or for a star shot. A sun shot isnearly as easy to do as a star shot and has the distinctadvantage of being able to be performed at anyconvenient time during the normal run of traverse.Sighting on the sun using an electronic theodolite or totalstation requires a solar filter, a fairly low-priced item. Likethe star shot, the hour-angle sunshot method requiresprecise time but does not require corrections fortemperature, barometric pressure, curvature andrefraction as does the Altitude Method. However, theAltitude Method’s results for sun sighting aren’t quite asaccurate as those of the Hour-Angle Method. Inpreparation for this event, all three of these commonmethods for determining Astronomic North were usedby the author over the past 18 months at Station“Compass Ref.Compass Ref.Compass Ref.Compass Ref.Compass Ref.” A brief comparison of the threeindependent results is included further along in thisarticle. In order to obtain acceptable results, any methodof celestial observation requires an instrument in goodadjustment with sensitive leveling bubbles. The steepzenith angles demand it.

In retracement matters, knowing how to perform anyof these easy surveying tasks, and using the date of adeed’s compass survey gleaned from research, will helpthe Surveyor to closely determine what the MagneticDeclination was at the time anoriginal compass survey wasconducted. Calculating the Astro-nomic North bearing from a linebetween original survey markersand comparing it with themagnetic bearing given in thedeed will yield the originalsurvey’s magnetic declination. Awise Surveyor will check thatdeclination against other originalmarkers or good markers inoriginal locations, if they can befound. Applying that correctionto the rest of the deed’s bearingswill greatly aid a modern Surveyorin retracing an original Surveyor’sfootsteps.

In the spirit of objectivefairness and genuine respect, it

should be noted that excellent, reproducible ruralcompass surveys are still being conducted in variousplaces throughout the U.S., mostly in forestryapplications. Galtjo GeertsemaGaltjo GeertsemaGaltjo GeertsemaGaltjo GeertsemaGaltjo Geertsema and the late Henry SipeHenry SipeHenry SipeHenry SipeHenry Sipeof West Virginia are two modern, excellent compasssurveyors. In fact, F. Henry Sipe’s, F. Henry Sipe’s, F. Henry Sipe’s, F. Henry Sipe’s, F. Henry Sipe’s book Compass LandCompass LandCompass LandCompass LandCompass LandSurveyingSurveyingSurveyingSurveyingSurveying makes a wonderful addition to any landsurveyor’s library of reference material.

Controversies arising from the differences inadjoining or connecting surveys made necessary theestablishment of (to quote the late Richard CooperRichard CooperRichard CooperRichard CooperRichard Cooper,Salisbury surveyor and Surveyor of the Year 1980) “…anunquestioned place where the deviation of the magneticneedle could be checked against the true meridian…”and where the surveyors could check their chains. [Thewidely-respected Mr. Cooper wrote a great article aboutthe Salisbury Stones in the Maryland Society ofSurveyors Newsletter, Volume 20, No. 3, 1993] In short,the granite markers were installed to provide a localstandard for both an angular check and a measurementcheck, a calibration baseline, if you will. Many of theorders for the surveys of lands that were issued by no-longer-existing Courts of Equity (a.k.a. Chancery)Courts of Equity (a.k.a. Chancery)Courts of Equity (a.k.a. Chancery)Courts of Equity (a.k.a. Chancery)Courts of Equity (a.k.a. Chancery)required that the Court’s Surveyor register hisinstruments and check the declination of his compass atthe meridian baseline before he started each court-ordered survey.

As previously mentioned, the City of Frederick hadalready experienced the discomforts of poorly matchingcompass surveys as far back as 1820. Something had to be

done to establish a local, easilyaccessible StandardStandardStandardStandardStandard for surveys.Maryland Geological SurveyMaryland Geological SurveyMaryland Geological SurveyMaryland Geological SurveyMaryland Geological Surveyrecords indicate that theFrederick County Compass Me-ridian Stones were installed byU.S. Coast and Geodetic SurveyU.S. Coast and Geodetic SurveyU.S. Coast and Geodetic SurveyU.S. Coast and Geodetic SurveyU.S. Coast and Geodetic Surveyin 1896, as were the two stonesinstalled that year in the City ofSalisbury, Wicomico County,Maryland. Records further notethat USC&GS used a U.S. CoastU.S. CoastU.S. CoastU.S. CoastU.S. Coastand Geodetic Survey Magne-and Geodetic Survey Magne-and Geodetic Survey Magne-and Geodetic Survey Magne-and Geodetic Survey Magne-tometertometertometertometertometer, an AltazimuthAltazimuthAltazimuthAltazimuthAltazimuth precisetransit and a Meantime Chro-Meantime Chro-Meantime Chro-Meantime Chro-Meantime Chro-nometernometernometernometernometer.

In the 1894 picture of thesecelestial observation instruments,note in particular some of thespecial characteristics of the

The magnetometer and the altazimuthinstrument.




Altazimuth transit. It had a large, extra-sensitive levelbubble at the top, a very large vertical circle witheyepiece, and several other attachments for celestialobservations including a right-angle eyepiece.

The star PolarisPolarisPolarisPolarisPolaris can be still be seen from the Stone“South Magnetic,South Magnetic,South Magnetic,South Magnetic,South Magnetic,” so it seems likely that PolarisPolarisPolarisPolarisPolaris wasused directly instead of a solar observation. It seems thatit would have been more accurate, too, since a solar-reference line error, even using USC&GS methods andadvanced equipment for that time period, couldapproach a minute of arc or more. NathanielNathanielNathanielNathanielNathanielBowditch’sBowditch’sBowditch’sBowditch’sBowditch’s (recall the Compass or BowditchBowditchBowditchBowditchBowditch Method oftraverse adjustment) Altitude Method, as explained in thebook Practical American Navigator, adapted for land use,was the solar computation method of choice for LandSurveyors until recent times, when common availabilityof ultra-precise time made the more accurate Hour-Hour-Hour-Hour-Hour-Angle MethodAngle MethodAngle MethodAngle MethodAngle Method practical and easy.

OBSERVATIONS

The answer to the question: “Which one is PolarisPolarisPolarisPolarisPolaris?” is“the end star in the tail of Ursa MinorUrsa MinorUrsa MinorUrsa MinorUrsa Minor (Little Bear), morecommonly known as The Little DipperThe Little DipperThe Little DipperThe Little DipperThe Little Dipper.” But ChapterSurveyors will have to take an astronomer’s word for it,because in downtown Frederick with all that backgroundlighting, we couldn’t see enough stars in that constellationto identify it. In addition, PolarisPolarisPolarisPolarisPolaris, at Magnitude 2.0, doesn’tshine brightly enough in the heavenly canopy to drawattention to itself. But it is handy for Northern Hemisphere

Surveyors (PolarisPolarisPolarisPolarisPolaris can’t be seen from the SouthernHemisphere locations because of Earth’s curvature) toobserve this particular star for several good reasons. It hasthe distinction of being close to the North Celestial PoleNorth Celestial PoleNorth Celestial PoleNorth Celestial PoleNorth Celestial Pole,seeming to track about a 1° radius around AstronomicNorth. Because of the star’s proximity to the Pole andbecause the Earth’s polar axis and equator are projectedonto the Celestial Sphere, the Surveyor’s own Latitudebecomes another way of locating Polaris. By subtracting hisposition’s Latitude angle from 90°, i.e., Co-latitude, andusing his compass for approximate direction, the Surveyorwill see that the resulting zenith angle is close to wherePolarisPolarisPolarisPolarisPolaris sits in the heavens. The zenith angle, while steep, iswithin the operating range of a theodolite. PolarisPolarisPolarisPolarisPolaris can beobserved without using a diagonal eyepiece attachment.Although other stars, such as AntaresAntaresAntaresAntaresAntares, CapellaCapellaCapellaCapellaCapella, SiriusSiriusSiriusSiriusSirius andRegulusRegulusRegulusRegulusRegulus could also be used, if not masked by the localhorizon or vegetation, PolarisPolarisPolarisPolarisPolaris is most often the star ofchoice.

There are two heavenly markers that can be used forguidance in locating the “Pole Star.” Ursa MajorUrsa MajorUrsa MajorUrsa MajorUrsa Major, the “BigDipper” is easily recognized and provides 3 stars foralignment. CassiopeiaCassiopeiaCassiopeiaCassiopeiaCassiopeia, the “lazy W” constellation, lies onthe other side of the Celestial Pole and provides one star.For illustration, please refer to the Chart to Locate Polaris.Rotate the chart until the words “Northern Sky at EasternElongation” are at the bottom. It will then represent theapproximate configuration of the sky at the NorthCelestial Pole as we saw it on the night of October 11,2003, between 8-10 p.m.

The star chart to locate Polaris.




Eastern or Western Elongation events are optimal timesto sight PolarisPolarisPolarisPolarisPolaris because the star appears to be traveling in anorth-south direction through a counter-clockwiserotation. The Surveyor doesn’t have to turn the tangentscrew very actively to track the star, and it is much easier torecord the instant of time that the star appears to move ontothe instrument crosshairs. Please note the use of the word“appears.” The star isn’t moving; we are. But for ease ofunderstanding and for calculations, some of Earth’scharacteristics, such as the equator, the axis, etc., areprojected outward onto an imaginary surface called theCelestial Sphere.

But the truth of the matter, as far as being able to locatePolarisPolarisPolarisPolarisPolaris, is that we cheated. Having previously performedboth an Altitude Method and an Hour-Angle Method SunShot from “Compass Ref” in order to establish a GridAzimuth to City Hall’s weathervane, we knew exactlywhere PolarisPolarisPolarisPolarisPolaris would appear in the heavens before the Hut

was erected. In fact, we had to know, since there is only onecelestial observation slot in only one of the roof panels ofthe hut, and it is just a few inches wide. Therefore, any usersof this particular celestial observatory must accurately alignthe slot during the daylight erection so that the subject starwill appear in the roof panel opening when darkness hasfallen.

The late Ralph DonnellyRalph DonnellyRalph DonnellyRalph DonnellyRalph Donnelly, (Past President of MSS andSurveyor of the year 1986))))) built our Hut nearly 20 years ago.He based his design on clues found in Mason’sMason’sMason’sMason’sMason’s and Dixon’sDixon’sDixon’sDixon’sDixon’sown notes and reports and finished the rest from theprompts of his own genius. Ralph’sRalph’sRalph’sRalph’sRalph’s resulting full-scaleportable model is made up of 4 foot wide, 6 foot highwooden panels which connect to form a circleapproximately 12 feet in diameter, and 8 foot longtriangular roof panels that rise in the center, converging ina conical shape. Once in place, the Hut’s composite roofdesign and heavy wooden weight make it essentiallyimpossible to rotate. Also, a celestial observation requiresnot one but two lines, one to the star, of course, and one toa traverse backsight. The Hut’s door must be aligned towardthe backsight, in order to transfer a celestial azimuth ontothe land.

Built in 1984 for a Blair’s Valley Mason-DixonCelebration, Ralph’sRalph’sRalph’sRalph’sRalph’s Hut was eventually given to otherenthusiasts Bob Gauss Bob Gauss Bob Gauss Bob Gauss Bob Gauss (Past President of MSS and Surveyorof the year 1997) and his two sons, Chris Chris Chris Chris Chris and Jim Jim Jim Jim Jim, to use asa centerpiece in their Emmitsburg’s Mason-Dixon FallFestival. ChrisChrisChrisChrisChris has assumed the mantle of responsibility andhas taken good care of it. The Hut was also displayedprominently at the Rendezvous ’02Rendezvous ’02Rendezvous ’02Rendezvous ’02Rendezvous ’02 in Gettysburg,Pennsylvania, Chas Langelan’s Chas Langelan’s Chas Langelan’s Chas Langelan’s Chas Langelan’s (Past President of MSS andSurveyor of the year 2003) incredible joint conference.Ralph Ralph Ralph Ralph Ralph would have been gratified to know that his Hut hasfinally been used, for the first time since its manufacture, forits manifest purpose, not as an interesting model, but by realSurveyors for an actual star observation. We are grateful forand yet humbled by Ralph’s unquenchable intellectualcuriosity, which is evidenced by the fact that the Hut stillserves his chosen profession today.

OBSERVATIONS ON POLARIS

The high cloud cover, which had been prevalentthroughout the day, began to clear in the southern sky asthe sun set. Seven o’clock; then seven-thirty; then darkness.Clouds still obscured our northern heavenly target. RobRobRobRobRobKundrick Kundrick Kundrick Kundrick Kundrick and crew practiced a new technique in precisetiming. By calling Station WWV Station WWV Station WWV Station WWV Station WWV (303) 499-7111 on his cellphone and turning up the volume, all could hear the timeticks and the announcer’s voice calling out UTCUTCUTCUTCUTC

Erecting the Hut – (L to R): Matt Brien, Wayne TwiggMatt Brien, Wayne TwiggMatt Brien, Wayne TwiggMatt Brien, Wayne TwiggMatt Brien, Wayne Twigg(kneeling), Rob Kundrick, Bob Pasley, T.J. Frazier Rob Kundrick, Bob Pasley, T.J. Frazier Rob Kundrick, Bob Pasley, T.J. Frazier Rob Kundrick, Bob Pasley, T.J. Frazier Rob Kundrick, Bob Pasley, T.J. Frazier andDr. Kenn Starr.Dr. Kenn Starr.Dr. Kenn Starr.Dr. Kenn Starr.Dr. Kenn Starr.

The Mason-Dixon Hut erected in Baker Park – Note theobservation slot in the roof.




(Coordinated Universal Time, a.k.a. Greenwich Civil Time).The double tick came on the 12th second, indicating a DUTDUTDUTDUTDUTcorrection of -0.4 seconds. This DUTDUTDUTDUTDUT correction is appliedto UTCUTCUTCUTCUTC to yield UT1UT1UT1UT1UT1 time. UT1UT1UT1UT1UT1 is also known as EarthRotation Time and is recommended for celestialobservations. Several calls were necessary to begin thestopwatch at exactly zero seconds. To maximize visionrecovery during the blackout conditions inside the Hut, theSurveyors drew on their military training experience andused several red lanterns and lights.

The instrument of choice that evening was a TopconTopconTopconTopconTopconET-1ET-1ET-1ET-1ET-1. A beautifully smooth 1-second total station, the ET-1ET-1ET-1ET-1ET-1has two-level internal lighting which illuminates not onlythe externaldisplay panelsbut the inter-nal cross-hair.It has extrasensitive level-ing bubbles.There are noswitches to flipor buttons topush. Thosecharacteristics,which may dis-turb sensitivesightings, arereplaced bye l e c t r o n i cs w i t c h e swhich func-tion when theoperator’s fin-ger interrupts

an infrared light beam. The instrument requires extrapower which was supplied by a 12-volt battery. The ET-1ET-1ET-1ET-1ET-1was convenient and easy to use. George Nagel George Nagel George Nagel George Nagel George Nagel had offeredthe use of his Wild T-2 Wild T-2 Wild T-2 Wild T-2 Wild T-2, a good 1-second instrument wouldhave also performed well.

Eight o’clock. The clouds still refused to give up theirposition. And then, as the coolness of evening began tospread, came the clearing. Almost miraculously, the cloudsbegan to dissipate from east to west, as if a curtain was beingdrawn aside. Having first studied star charts, the ChapterSurveyors knew that CassiopeiaCassiopeiaCassiopeiaCassiopeiaCassiopeia would be located on theeast side of the Celestial Pole between 7:30 and 8:00 p.m.The stars of the “Lazy W” constellation appeared, one byone. PolarisPolarisPolarisPolarisPolaris was next. The Surveyors entered the Hut totake their place at the instrument, which had already beenset up over “Compass RefCompass RefCompass RefCompass RefCompass Ref”. They had the angle clockwisefrom the weathervane as well as the calculated zenith angle.Matt BrienMatt BrienMatt BrienMatt BrienMatt Brien was the first to see the object of our effortsthrough the ET-1’s telescope. The PolarisPolarisPolarisPolarisPolaris observations hadfinally begun.

Standard direct and reverse sets were turned by nearlyeveryone, with Surveyors switching between the roles ofInstrument Operator, Note Keeper and Time Keeper.

CALCULATIONS AND COMMENTS

October’s Ephemeris page and one of the Chapter’sactual computation sheets for one of the field sets of theChapter’s Polaris observations are displayed below.

The October 2003 ephemeris.

Inside the hut, preparing for the observations: (L to R)Mike Burtner, Wayne Twigg, Rob Kundrick Mike Burtner, Wayne Twigg, Rob Kundrick Mike Burtner, Wayne Twigg, Rob Kundrick Mike Burtner, Wayne Twigg, Rob Kundrick Mike Burtner, Wayne Twigg, Rob Kundrick and T.J.T.J.T.J.T.J.T.J.FrazierFrazierFrazierFrazierFrazier, with the Topcon ET-1 in the foreground.




As can be seen by examining the calculationsheet and the EphemerisEphemerisEphemerisEphemerisEphemeris page, the GreenwichGreenwichGreenwichGreenwichGreenwichHour Angle (GHA) Hour Angle (GHA) Hour Angle (GHA) Hour Angle (GHA) Hour Angle (GHA) for zero hours on October 11,2003, was transposed right from the Ephemerispage. We also lifted the zero hour GHA for the nextday, October 12 in order to interpolate to get thetime of the observation, or the Local GHALocal GHALocal GHALocal GHALocal GHA, withinthe 24 hour time period. We did the same withPolaris’ DeclinationPolaris’ DeclinationPolaris’ DeclinationPolaris’ DeclinationPolaris’ Declination. The Local Hour AngleLocal Hour AngleLocal Hour AngleLocal Hour AngleLocal Hour Angle(LHA)(LHA)(LHA)(LHA)(LHA)is obtained simply by subtracting theLongtitudeLongtitudeLongtitudeLongtitudeLongtitude of the place of our observation fromthe computed GHAGHAGHAGHAGHA. The LHALHALHALHALHA is Angle P in thefamiliar PZS triangle.

The azimuth of PolarisPolarisPolarisPolarisPolaris is then computed. Ourcomputed PolarisPolarisPolarisPolarisPolaris azimuth has a positive sign becausethe star was on the right side of the North CelestialNorth CelestialNorth CelestialNorth CelestialNorth CelestialPolePolePolePolePole during the times of our observations.

Next we computed the Astronomic AzimuthAstronomic AzimuthAstronomic AzimuthAstronomic AzimuthAstronomic Azimuth of

our backsight line by applying our field-turned setof angles. Converting the result to a bearing andcomparing it with our compass bearing to thebacksight gives us the Local Magnetic Declina-Local Magnetic Declina-Local Magnetic Declina-Local Magnetic Declina-Local Magnetic Declina-tion.tion.tion.tion.tion. The Surveyor should then apply the LaPlaceLaPlaceLaPlaceLaPlaceLaPlaceCorrectionCorrectionCorrectionCorrectionCorrection to the Astronomic AzimuthAstronomic AzimuthAstronomic AzimuthAstronomic AzimuthAstronomic Azimuth toascertain the Geodetic AzimuthGeodetic AzimuthGeodetic AzimuthGeodetic AzimuthGeodetic Azimuth. The LaPlaceLaPlaceLaPlaceLaPlaceLaPlaceCorrectionCorrectionCorrectionCorrectionCorrection is given to the Surveyor by his use ofNGS’s DEFL99NGS’s DEFL99NGS’s DEFL99NGS’s DEFL99NGS’s DEFL99. This small but important correc-tion varies from place to place according to theproximity of mountain masses. The LaPlaceLaPlaceLaPlaceLaPlaceLaPlaceCorrectionCorrectionCorrectionCorrectionCorrection is added (observing signs) to theAstronomic AzimuthAstronomic AzimuthAstronomic AzimuthAstronomic AzimuthAstronomic Azimuth to yield the GeodeticGeodeticGeodeticGeodeticGeodeticAzimuthAzimuthAzimuthAzimuthAzimuth.

A Grid AzimuthGrid AzimuthGrid AzimuthGrid AzimuthGrid Azimuth, which usually is theSurveyor’s reason behind his performing a celestialobservation, for the backsight line is determined byfirst calculating the Mapping (or Convergence)Mapping (or Convergence)Mapping (or Convergence)Mapping (or Convergence)Mapping (or Convergence)AngleAngleAngleAngleAngle for the place of observation. Every MarylandSurveyor knows the Central MeridianCentral MeridianCentral MeridianCentral MeridianCentral Meridian of Marylandto be 077°00’00” West Longitude. He thensubtracts his Longitude from that of the CentralCentralCentralCentralCentralMeridianMeridianMeridianMeridianMeridian and multiplies the result by Maryland’sZone Constant for NAD83Zone Constant for NAD83Zone Constant for NAD83Zone Constant for NAD83Zone Constant for NAD83, which is 0.62763413.He also knows that if his position lies west of theCentral MeridianCentral MeridianCentral MeridianCentral MeridianCentral Meridian, his Mapping AngleMapping AngleMapping AngleMapping AngleMapping Angle has anegative sign and if to the east, a positive one. Aftercomputing the Mapping AngleMapping AngleMapping AngleMapping AngleMapping Angle, he then subtracts(again observing signs) it from the GeodeticGeodeticGeodeticGeodeticGeodeticAzimuthAzimuthAzimuthAzimuthAzimuth which give him the desired GridGridGridGridGridAzimuthAzimuthAzimuthAzimuthAzimuth.

For purposes of comparing our differentcelestial observation results, we found theAstronomic BearingAstronomic BearingAstronomic BearingAstronomic BearingAstronomic Bearing from “Compass RefCompass RefCompass RefCompass RefCompass Ref” to CityHall’s weathervane to be the following, accordingto the three methods: Polaris Hour-Angle MethodPolaris Hour-Angle MethodPolaris Hour-Angle MethodPolaris Hour-Angle MethodPolaris Hour-Angle Method= S88°21’16.7”E; Sun Hour-Angle MethodSun Hour-Angle MethodSun Hour-Angle MethodSun Hour-Angle MethodSun Hour-Angle Method =S88°21’49.3”E; and Sun Altitude MethodSun Altitude MethodSun Altitude MethodSun Altitude MethodSun Altitude Method =S88°18’53”E. The results of the Sun AltitudeSun AltitudeSun AltitudeSun AltitudeSun AltitudeMethodMethodMethodMethodMethod should have been much closer to the otherresults but was probably adversely affected byusing a lower-precision theodolite with lesssensitive leveling vials.

The calculation sheet presented in this article isonly one of the several sets prepared by theSurveyors of the Appalachian ChapterAppalachian ChapterAppalachian ChapterAppalachian ChapterAppalachian Chapter. EachSurveyor’s observation have been calculatedseparately and will be averaged, with outliers, ifany, removed. The next phase of the CompassCompassCompassCompassCompassMeridian Stones of Frederick, MarylandMeridian Stones of Frederick, MarylandMeridian Stones of Frederick, MarylandMeridian Stones of Frederick, MarylandMeridian Stones of Frederick, Maryland project

One of the completed observation calculation sheets.




will take place when the Chapter Surveyors againconverge on Baker Park to run a traverse throughthe Stones so that the parameters for the resettingof “South MagneticSouth MagneticSouth MagneticSouth MagneticSouth Magnetic” can be determined. After that,the disturbed century old marker can reoccupy itscorrect position and once again provide a StandardStandardStandardStandardStandardfor correctness. We all could benefit from thelessons these Stones can teach.

CHAPTER APPRECIATION

The Chapter thanks Past President of MSS andSurveyor of the year 1997 Marc Cheves, whostopped in early on his way to a work relatedengagement later that evening, Chapter ViceChairman T. J. FrazierT. J. FrazierT. J. FrazierT. J. FrazierT. J. Frazier (who selflessly gave himselfto review a huge amount of documentation, as wellas donating his truck and trailer for the two-waytransportation of the Hut), Bob Banzhoff, , Bob Banzhoff, , Bob Banzhoff, , Bob Banzhoff, , Bob Banzhoff, (Vice-President of MSS), Gordon Conner, Gordon Conner, Gordon Conner, Gordon Conner, Gordon Conner, ChapterChairman Rob Kundrick Rob Kundrick Rob Kundrick Rob Kundrick Rob Kundrick for coordinating theevent, Matt Brien, , Matt Brien, , Matt Brien, , Matt Brien, , Matt Brien, Affiliate Committee ChairmanBob PasleyBob PasleyBob PasleyBob PasleyBob Pasley (another unsung hero), Dave Ritchie,, Dave Ritchie,, Dave Ritchie,, Dave Ritchie,, Dave Ritchie,Mike Burtner, Wayne Twigg Mike Burtner, Wayne Twigg Mike Burtner, Wayne Twigg Mike Burtner, Wayne Twigg Mike Burtner, Wayne Twigg and last, butdefinitely not least, Chas Langelan, , Chas Langelan, , Chas Langelan, , Chas Langelan, , Chas Langelan, MSS Past-President and Surveyor of the year 2003, whostopped by with a surveyor’s compass in hand toshare enthusiasm, assure us of his support, and tocheck whether we had properly aligned theobservation port in the roof.

Kenn StarrKenn StarrKenn StarrKenn StarrKenn Starr, an amazing man with a long,distinguished historian’s career, was right therewith us, wielding a hammer and pounding pegs tohelp erect the Hut. His work of locating andcataloging Stones-of-Interest, particularly his spe-cial technique of copying the etchings on them, isextremely valuable and already occupies a place inour local history, and has earned him a specialappreciation as a great friend of the Chapter. KennKennKennKennKennis one of those rare people whose accomplish-

ments and credentials are only exceeded by hisfriendliness, intellectual curiosity, humility, quietmaturity and behind-the-scenes support. What anexample for us all!

City Alderman Marcia HallCity Alderman Marcia HallCity Alderman Marcia HallCity Alderman Marcia HallCity Alderman Marcia Hall is deeply interestedin the Chapter’s Meridian Stones Project, as isNancy PossNancy PossNancy PossNancy PossNancy Poss, City Public Relations Director. Bothwere very helpful in the process of allowing theChapter to erect the Hut in Baker Park. LongtimeCity electrical expert Bill Scheetz Bill Scheetz Bill Scheetz Bill Scheetz Bill Scheetz gave us somegood advice concerning the handling of nearbystreet lamps and tennis court lighting. KeithKeithKeithKeithKeithBrownBrownBrownBrownBrown made comfort stations and park accessavailable to us. Jesse GoodeJesse GoodeJesse GoodeJesse GoodeJesse Goode, Park Police, was kindenough to allow our unusual activities to proceedundisturbed. The Chapter gratefully extends itsthanks to these outstanding men and women.

STAY TUNED!

The Appalachian Chapter is planning to resetSouth MagneticSouth MagneticSouth MagneticSouth MagneticSouth Magnetic and to rededicate both MeridianMeridianMeridianMeridianMeridianStonesStonesStonesStonesStones with a formal ceremony involving FrederickFrederickFrederickFrederickFrederickCityCityCityCityCity officials at the site at City Hall. The Chapterhas undertaken this long term project with thesegoals as their objectives: to give something back tothe community, the City and the Public byrestoring the stones and calling attention to them,to raise the public profile of the surveyingprofession, to enhance the public image ofsurveyors, to promote the public image ofsurveyors as professionals, and to learn something.The Maryland SurveyorThe Maryland SurveyorThe Maryland SurveyorThe Maryland SurveyorThe Maryland Surveyor will be there, as always, todocument these efforts.

(Editor’s Note: R. Wayne TwiggR. Wayne TwiggR. Wayne TwiggR. Wayne TwiggR. Wayne Twigg is RecordingSecretary of the Appalachian Chapter. This is thesecond of a series of articles he has been writingto document the progress of the work on theMeridian Stones for The Maryland Surveyor.)

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The MARYLAND SURVEYOR - theamericansurveyor.com · The MARYLAND SURVEYOR ... Compensation must be ... solar or star observation to Magnetic North from the compass observation