The Popular and Scientific Reception of the Foucault Pendulum in

Transcription

The Popular and Scientific Reception of the Foucault Pendulum in
The Popular and Scientific Reception of the Foucault Pendulum in the United States
Author(s): Michael F. Conlin
Reviewed work(s):
Source: Isis, Vol. 90, No. 2 (Jun., 1999), pp. 181-204
Published by: The University of Chicago Press on behalf of The History of Science Society
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The
Popular
Reception
of
in
the
the
and
Scientific
Foucault
United
Pendulum
States
By Michael F. Conlin*
ABSTRACT
In 1851 J. B. L. Foucaultprovidedthe firstmechanicaldemonstrationof the earth'sdiurnal
rotationwith a vibratingpendulum.He performedthe experimentin the Pantheonin Paris,
sparkinga pendulummania that raged across Europe and the United States. The interest
in the Foucaultpendulumprovides an opportunityto examine the popularizationof physical science in the antebellumUnited States. Laypersonsattendedpublic demonstrations,
performedtheirown demonstrations,anddisputedthe principlesof the Foucaultpendulum.
Their participationin physical science made them part of the American scientific community. These lay scientists performedmost of the public demonstrationsof the experiment. Some researchersperformedpublic demonstrations,but others avoided this opportunity to popularize, deeming it unseemly to participate in pendulum mania. The
geographicaldistributionof interestin the experimentchallenges assertionsmade by historians about the relative level of scientific activity in the New England, mid-Atlantic,
southern,and western regions of the United States.
FROM APRIL TO SEPTEMBER 1851 Americans joined Europeans in what Putnam's
Magazine described as the "pendulum mania" sparked by Jean Bernard Leon Foucault's exhibition of the earth's diurnal rotation with a vibrating pendulum. (See Frontispiece.) A range of Americans-from distinguished scientists to unschooled enthusiastsrepeated the experiment in private and before crowds in at least twenty-five cities and
towns. Private repetitions were conducted in houses, laboratories, and places of business;
public demonstrations were conducted in government buildings, hotels, universities, and
* Departmentof History, 309 GregoryHall, 810 South Wright Street, Urbana,Illinois 61801.
I would like to thank H. RichardCrane,Jon B. Eklund,RobertW. Johannsen,Marc Rothenberg,Ronald B.
Smith, Winton U. Solberg, and WoodruffT. Sullivan III, as well as MargaretRossiter and the Isis referees. In
addition,I would like to thankthe various manuscriptlibrariesthat allowed me to quote from their collections:
The Syndics of the CambridgeUniversity Library;Rensselaer Polytechnic InstituteArchives and Special Collections; Beinecke Rare Book and ManuscriptLibrary,Yale University;SmithsonianInstitutionArchives;Harvard University Archives; GeorgetownUniversity Special Collections; and South CarolinaLibrary,University
of South CarolinaArchives. Moreover,I would like to thankthe Centerfor History of Physics at the American
Instituteof Physics for awardingme a grant-in-aidto conduct researchon this project.
Isis, 1999, 90:181-204
C 1999 by The History of Science Society. All rights reserved.
0021-1753/99/9002-0001$02.00
181
_FI
Illustrationof Jean Bernard L6on Foucault's demonstration at the Pantheon in Paris
from an unidentified French periodical, in St6phane Deligeorges, Foucault et ses
pendules (Paris: Editions Carr6, 1990), page 55.
182
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
churches.Some who observed or performedthese exhibitionsdescribedthe experimentas
"interesting,""curious,""beautiful,"and "sublime."ManyAmericanswroteto newspapers
demandingdemonstrations,requestingexplanations,and advancingtheories of the Foucault pendulum.Commentators,rangingfrom scientists to newspapereditors,marveledat
what James D. Dana, professorof geology at Yale College, called the "universalattention
and interest"excited by the experiment."Everybody is delighted with the phenomenon,"
a newspapercolumnist noted, "andall are eager to understandit."'
Because much of the popular reaction to physical science was modest and hence is
invisible to historians,interestin the Foucaultpendulumprovides a valuable opportunity
to examine the popularizationof physical science in the antebellumUnited States. More
than twenty years ago, Nathan Reingold sought to distinguish the American scientific
communityfrom the learnedcultureof professionalsand merchantsand from the vernacular culture of farmersand mechanics. He divided those interestedin science into three
groups:"researchers,"who published scientific work; "practitioners,"
who made theirliving from science; and "cultivators,"who joined scientific societies. AlthoughDaniel Goldstein expandedthe base of the Americanscientificcommunityto includethe naturalhistory
collectors of the SmithsonianInstitution,I arguethatit mustbe expandedfurtherto include
members of the learned culture and members of the vernacularculture who performed
demonstrationsand disputed the principles of the Foucault pendulum. Members of the
entire scientific community participatedin the pendulum mania. Cultivatorsand practitioners conductedmost of the public demonstrations.Some researchersperformedpublic
demonstrationsand providedpopularexplanations,but many avoided the opportunityto
popularize physical science offered by the Foucault pendulum. Reflecting regional and
professionalbiases, New Englandresearcherswho participatedin pendulummaniaignored
contributionsmade by researchersfrom otherregions of the United States as well as those
made by practitioners,cultivators,and others.Two of the leading popularizersof physical
science declined to participatein pendulum mania, perhaps because the field was so
crowded with demonstrators.Moreover,the widespreaddistributionof interestin the experiment challenges assertions made by historians about the relative level of scientific
activity in various regions of the antebellumUnited States.2
Pendulum mania reflected the interest Americans had demonstratedin astronomical
phenomena since the early eighteenth century. Announcementsof eclipses and comets
regularlygraced the pages of American newspapers.No other physical science so completely capturedthe public imagination as astronomy. Five years before the pendulum
mania erupted,controversyover the discovery of Neptune had been a cause celebre in the
United States. In many ways the popularreception of the Foucaultpendulumparalleled
the popularreactionto the Neptunecontroversy.Like the Foucaultpendulum,the Neptune
1
"Foucault,the Academician,"Putnam'sMonthly:A Magazine of Literature,Science, and Art, 1856, 8:416421, on p. 419; [James D. Dana], "PhysicalDemonstrationof the Rotation of the Earthby Means of the Pendulum,"AmericanJournal of Science, 2nd Ser., 1851, 12:112-113, on p. 112; andNational Intelligencer,7 June
1851, p. 2.
2 NathanReingold, "Definitionsand Speculations:The Professionalizationof Science in America in the Nineteenth Century,"in ThePursuit of Knowledgein the EarlyAmericanRepublic:AmericanScientificand Learned
Societiesfrom Colonial Timesto the Civil War,ed. AlexandraOleson and SanbornC. Brown (Baltimore:Johns
Hopkins Univ. Press, 1976), pp. 38-51; Daniel Goldstein, " 'Yours for Science': The SmithsonianInstitution's
Correspondentsand the Shape of Scientific Communityin Nineteenth-CenturyAmerica,"Isis, 1994, 85:573599, on p. 573; Robert V. Bruce, "A Statistical Profile of American Scientists, 1846-1876," in NineteenthCenturyAmerican Science: A Reappraisal, ed. George H. Daniels (Evanston, Ill.: NorthwesternUniv. Press,
1972), p. 68; and Sally GregoryKohlstedt,TheFormationof the AmericanScientificCommunity:TheAmerican
Associationfor the Advancementof Science, 1848-1860 (Urbana:Univ. Illinois Press, 1976), pp. 200, 209-210.
MICHAELF. CONLIN
183
Figure 1. Portraitof Jean BernardL6onFoucault.
controversywas widely covered in American newspapers,was touted as a confirmation
of astronomicaltheory, and promptedDana to note that it was of "muchgeneral as well
as scientific interest."The Neptune controversyand the reception of the Foucaultpendulum, however, differed in the depth of public participation.Whereasthe Neptunecontroversy attractedonly researchers,the Foucaultpendulumattractedresearchers,practitioners,
cultivators,andothers.The Foucaultpendulum's popularitywas a resultof its highly visual
effect, its illustrationof a basic physical principle, its use of readily available apparatus,
and its ability to fascinateobservers.This last resultcan still be witnessed today at science
museums aroundthe world.'
FOUCAULT AND HIS PENDULUM
In France,Jean BernardLe6onFoucaultwas the leading experimentalphysicist of his day.
(See Figure 1.) While working on a clock with a conical pendulumto keep a telescope
continuously focused on a heavenly body during the long exposures requiredfor midnineteenth-centuryphotography,Foucaultplaced a steel rod in a lathe. After accidentally
I Brooke Hindle, The Pursuit of Science in RevolutionaryAmerica, 1735-1789 (Chapel Hill: Univ. North
Carolina Press, 1956), pp. 94-96, 156, 172; and Donald Zochert, "Science and the Common Man in AnteBellum America,"Isis, 1974, 65:448-486, on pp. 448-449. John G. Hubbell and RobertW. Smith, "Neptune
in America: Negotiating a Discovery," Journalfor the History of Astronomy, 1992, 23:261-291, on pp. 261264, found "interest"in but no "particularpopularreaction"to the Neptune controversy.
184
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
bumping the rod and causing it to vibrate, he noticed that the rod tended to maintainits
plane of vibrationeven when rotated.He perceived that if an oscillating pendulummaintainedits plane of vibration-as the rod did-it mightprovidea mechanicaldemonstration
of the earth's rotation.On 8 January1851 Foucault vibrateda pendulumtwo meters in
length. To his delight, the pendulum maintained its position while the floor gradually
moved along with the direction of the earth's rotation.4Discounting air resistance and
friction at the point of suspension, the only forces acting on Foucault's pendulumwere
the pull of gravity and the tension of the wire, so that it oscillated independentlyof the
earth's rotation.
On 3 FebruaryFoucaultrepeatedthe experimentbefore the Academie des Sciences in
the National Observatorywith a pendulum eleven meters in length. He determinedthat
the period for the apparentprecession of the plane of the pendulum's oscillation around
the circle describedby the pendulum's arc of oscillation varied by latitude:at the poles a
complete precessiontook almost exactly twenty-fourhours(one siderealday), at the equator there was no precession, and in between the poles and the equator the period was
inversely proportionalto the sine of the latitudewhere the pendulumoscillated. By graduating the radius of the circle described by the pendulum's arc of oscillation, Foucault
demonstratedthat the earthhad moved from the pendulum'splane of oscillation-compelling proof of the earth's rotationeven to an unscientificobserver.In March 1851 Foucault, at PresidentLouis Napoleon's request,performedthe experimentat the Pantheonin
Paris with a gigantic pendulumsixty-seven meters in length. This dramaticdemonstration
attractedlarge crowds and sparkedthe pendulummania in Europeand the United States.5
GREAT BRITAIN
Britons also exhibited great enthusiasmfor the Foucaultpendulum.In GreatBritain,the
pendulumvibratedbefore crowds in at least six cities. Londoners showed particularinterest, watching demonstrationsin at least five places. The Athenwumobserved that the
Foucaultpendulum"hasbeen the subject of so much popularnotice ... that it would be
needless to go into a particulardescriptionof its natureor object."In both Britainand the
United States, the most widely circulatedaccountof the experimentwas thatpublishedby
the London Globe on 5 April 1851. HeraldingFoucault's discovery as "one of the most
remarkableof the modem verificationsof theory,"the Globe observedthatthe experiment
aroused"feelings of profoundinterestand excitement."The earth'srotationwas "rendered
actuallyvisible to the crowds which daily flock to the Pantheonto witness this remarkable
experiment."The Globe incorrectlyreportedthat at the Pantheonthe pendulum'splane of
oscillation precessed at the rate of fifteen degrees per hour, making a complete revolution
every twenty-fourhours.6
On 8 April the London Timesreprintedthe Globe's account of Foucault's repetitionat
4HaroldL. Burstyn,"JeanBernardLeon Foucault,"in Dictionaryof ScientificBiography,ed. CharlesCoulston
Gillispie (New York: Scribner's, 1970), Vol. 5, pp. 84-87, on pp. 85-86.
5L6on Foucault, "Demonstrationphysique du mouvement de rotation de la terre au moyen du pendule,"
CompteRendu des Seances de l'Acade'miedes Sciences, 1851, 32:135-138; Journal des De'batsPolitiques et
Litiraires, 31 Mar. 1851, p. 3; StephaneDeligeorges, Foucault et ses pendules (Paris:Carr6,1995), pp. 49, 5459; Burstyn, "Foucault,"pp. 85-86; Henry Worms, The Earth and Its Mechanism:Being an Account of the
VariousProofs of the Rotationof the Earth (London, 1862), pp. 103-107; andWilliam Tobin and BrianPippard,
"Foucault,His Pendulum,and the Rotationof the Earth,"InterdisciplinaryScience Reviews, 1994, 19:326-337,
on pp. 327-328.
6Athenwum,14 June 1851, pp. 637-638; and London Globe, rpt. in London Times, 8 Apr. 1851, p. 7.
MICHAELF. CONLIN
185
the Pantheon,sparkinga correctionby JosephJ. Sylvester, a mathematicianand fellow of
the Royal Society. Unimpressedby the enthusiasmexcited by the Foucaultpendulumand
unsympatheticto the populardifficulty in understandingthe dependenceon latitudeof the
period of the apparentprecession of the pendulum,he pleaded that the "publicshould not
be so unreasonableas to expect thatevery conclusion or calculationadmitsof being made
clear to public apprehension."Warning that repetitions must be "conductedwith great
care,"Sylvester lamentedthat careless experimentershad brought"some discredit"to the
Foucault pendulumin Britain. "It is perfectly absurd,"he admonished,"for persons unacquaintedwith mechanicaland geometricalscience to presumeto make the experiment."
This "too-hastyrush at the experimentalverificationof Foucault's law may account for
some persons in England, whose opinions when given with due deliberationare entitled
to respect, having allowed themselves to express doubts (which I understand,however, to
have been since retracted)as to the truthof the law itself."7
Sylvester's discretionpreventedhim from namingGeorgeB. Airy, the astronomerroyal,
and the ReverendBaden Powell, Savilian Professorof Geometryat OxfordUniversity,as
the mistakenscientists. In privatecorrespondence,Airy had repeatedlydismissed the Foucault pendulumexperimentas a "fraud."He regardedthe latitude-dependentformulafor
the period of the apparentprecession of the pendulumas a "mathematicalcuriosityhaving
no applicationwhateverto the soi-disant experiment."Attendingno demonstrations,Airy
based his conclusion on oral accounts of the experiment.Concurringwith Airy, Powell
accepted the theory but held that as a "practicalquestion"the experimentwas "doubtless
open to every kind of doubt."After learning of successful demonstrationsby British scientists, Airy conducted his own experiments. Although it was possible to conduct the
experimentproperly,he concluded that the "difficultyof startinga free pendulum,so as
to make it vibrateat first in a plane, is extremely great."8
Although Airy and Powell kept their opinions private,popularjournalslearnedof their
rejection of the experiment.Linking Airy's and Powell's doubts to recent unsuccessful
popular demonstrationsof the experiment,these journals questioned the validity of the
Foucault pendulum. The London Literary Gazette recommendedcaution to those who
would attemptthe experimentbecause "personsunqualifiedby previoushabitsof research
and accurateinvestigation"had failed. The Literary Gazette knew of several exhibitions
"in which, to the horrorof the spectators,the earth has been shown to turn the wrong
way." The Illustrated London News expressed similar reservations, observing that the
"experimentis now giving rise to much controversy,and it is hardto conceive that there
is not some fallacy lurkingat the bottomof it." Parodyingthis controversy,Punch reported
that a correspondentnamed Swiggins had observed the earth's rotationin a mannerthat
should satisfy those "sceptical and obstinate"persons who doubted that it was visible.
After six cups of brandy,Swiggins did not need a pendulumto convince him thatthe earth
was spinning;he had only to look at the ceiling.9
Powell and Airy attemptedto disabuse the public of doubts concerning the Foucault
pendulum.On 9 May, Powell, a leading British popularizerof science, gave an address
7London Times, 8 Apr. 1851, p. 7, 11 Apr. 1851, p. 8, 26 Apr. 1851, p. 8.
8 George B. Airy to Baden Powell, 18 Apr. 1851, Airy to Powell, 23 Apr. 1851, Powell to Airy, 26 Apr. 1851,
GeorgeBidwell Airy Papers,Royal GreenwichObservatoryArchives, CambridgeUniversityArchives;andAiry,
"On the Vibrationof a Free Pendulumin an Oval Differing Little from a StraightLine," Memoirs of the Royal
AstronomicalSociety, 1851, 20:121-130, on p. 122.
9 LondonLiteraryGazette,rpt. in TrentonState Gazette, 14 June 1851, p. 2; IllustratedLondonNews, 3 May
1851, p. 345; and Punch, 1851, 20:191.
186
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
on the Foucaultpendulumat a public demonstrationof the experimentat the Royal Institution. Listing the repetitionsconductedby scientists in Britainand Europe,he noted that
the "accordanceof many of the results at different places within fair limits of error"
confirmedthe validity of the experiment.Powell cautioned,nevertheless,thatthe "sources
of errorare numerousand not easy to be effectually guardedagainst."He reasonedthat
"these causes of error"affected "many of the public repetitions"whose results did not
conform to theory. Powell also noted that Airy had confirmedthe experiment.On 9 May,
Airy had presentedhis results to the Royal AstronomicalSociety. Two months later,Airy
observedin an addressbefore the BritishAssociation for the Advancementof Science that
the Foucaultpendulumhad "excited very great attentionboth in Franceand England"by
"visibly proving, if proof were necessary,"the earth's rotation.Although now "certain"
that "Foucault'stheoryis correct,"Airy warnedthat "carefuladjustments"were necessary.
"Forwant of these the experimenthas sometimes failed."'0
THE UNITED STATES
The hesitance of British scientists to endorse the Foucault pendulum slowed American
receptionof the experiment.Whereaspendulummaniapeakedin Britainin April andMay,
it swept across the United States in May, June, and July. (See Figure 2.) In the midnineteenthcentury,Americansdependedupon Europeanscience for education,motivation,
and theory. While acknowledging this reliance and looking for approvalfrom Europe,
Americanscientists contendedthat they were the equals of any. Although James D. Dana
informedAmericanscientistsof the Foucaultpendulumin theAmericanJournalof Science
withoutmentioningthe Britishcontroversy,the Americanpublic followed the dispute.The
ScientificAmericanobserved that Foucault's pendulumwas the "subjectof much controversy in England,some are statingthat it is fallacious, othersprovingit to be the reverse."
A Pennsylvanianewspapernoted that "quitea discussion has been startedamong some of
the big guns of Europein regardto it-some contendingfor it, othersviolently opposing
it as a fallacy." Airy's endorsementof the experiment-which Americannewspapersand
periodicalsreprinted-invigorated Americaninterestin the Foucaultpendulum."
Americansknew of the Foucaultpendulumbefore they learnedof Airy's endorsement,
but since the LondonGlobe was their main source,the informationwas suspect.Fromlate
April to early May, Americansin almost every majorcity-Boston, Providence,Albany,
New York, Newark, Trenton,Pittsburgh,Philadelphia,Savannah,Charleston,St. Louis,
and San Francisco-first learned of the Foucault pendulumfrom the Globe's erroneous
account.In bilingualNew Orleans,Anglophoneswere informedof the Foucaultpendulum
by the Picayune's reprintof the Globe, while Francophoneswere apprisedof Foucault's
"experiencecurieux"by the Paris correspondentof the Courier de la Louisiane. Secular
journals, such as the ScientificAmerican and the InternationalMagazine, and religious
IOAtheneum,14 June 1851, pp. 637-638; Airy, "Vibrationof a Free Pendulum"(cit. n. 8); and George B.
Airy, "Address,"Report of the Twenty-firstMeeting of the BritishAssociationfor the Advancementof Science,
1852, 21:xxxix-liii, on p. xliii.
11Dana, "PhysicalDemonstrationof the Rotation of the Earth"(cit. n. 1), pp. 112-113; "Demonstrationof
the Earth's Rotation,"ScientificAmerican, 1851, 6:289; Miners' Journal and Pottsville General Advertiser,7
June 1851, p. 2; "BritishScientific Association, &c.," Sci. Amer., 1851, 6:362; and Providence Journal, 8 Aug.
1851, p. 2.
MICHAELF. CONLIN
187
M~~~~
from"Demonstration
Figure 2 Illustration
of the Earth'sRotation,"
ScientificAmerican,1851, 6:289.
journals,such as the Trumpetand UniversalistMagazineand the ChristianWatchmanand
Reflector,also reprintedthe Globe's account.12
Several Americans made efforts to remedy the Globe's errors.People in and around
Boston firstlearnedof the Foucaultpendulumfrom the Boston Evening Traveller'sreprint
of the Globe, but Benjamin A. Gould, a Cambridgeastronomerand editor of the Astronomical Journal, submitteda correctionto the Evening Travelleras a public service because the Globe's account was "incorrect"and "unintelligible."Gould's article was not
widely reprinted,unfortunately,and it had minimal impact on popularreception of the
Foucaultpendulum.Indeed,Gould's accountdid not disabuseall of the Boston newspapers
of the Globe's errors.Two otherBoston newspapers,the Morning Commonwealthand the
Evening Transcript,repeatedthese mistakes. In Washington,readerslearned of the Foucault pendulum on 22 April when the Paris correspondentof the National Intelligencer
reportedon the "beautifulexperimentwhich all Paris is flocking to the Pantheonto see,
and which is being repeatedall over France and Europe."On 7 April the correspondent
had visited the Pantheon to see the demonstration,but he waited until publication of
12
Boston Evening Transcript,26 Apr. 1851, p. 2; Providence Journal, 20 May 1851, p. 1; Albany Journal,
26 Apr. 1851, p. 2; New YorkHerald, 24 Apr. 1851, p. 2; NewarkAdvertiser,29 Apr. 1851, p. 2; TrentonState
Gazette,28 Apr. 1851, p. 1; PittsburghGazette,29 Apr. 1851, p. 1; Cummings'EveningBulletin (Philadelphia),
26 Apr. 1851, p. 3; SavannahRepublican,24 Apr. 1851, p. 2; CharlestonCourier,30 Apr. 1851, p. 2; Missouri
Republican(St. Louis), 5 May 1851, p. 2; San Francisco Herald, 27 June 1851, p. 2; Picayune (New Orleans),
1 May 1851, p. 1; Courier de la Louisiane (New Orleans),21 Apr. 1851, p. 2; Sci. Amer., 1851, 6:267; International Magazine of Literature,Art, and Science, 1851, 3:296; Trumpetand Universalist Magazine, 1851,
23:208; and ChristianWatchmanand Reflector, 1851, 32:80.
188
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
Foucault'spresentationof the experimentto the Academiebefore sending a reportto avoid
the "palpablygross errors"that appearedin the Globe and other newspapers. He also
translatedFoucault's notice into English. The National Intelligencer's account was not
only the earliestAmericanannouncementof the experiment;it was also the most complete.
Lacking a Paris correspondent,the WashingtonRepublic carriedthe Globe's account almost a month after the National Intelligencerbroke the story.13
THE RISE OF PENDULUM MANIA
In addition to the London Globe's widely reprintedaccount, newspaperreportsof local
demonstrationsof the experimentwere an importantimpetus for pendulummania.Learning of the Foucaultpendulumfrom the NewarkAdvertiser'sreprintof the Globe, H. D. V.,
a farmerfrom Plainfield,New Jersey,vibrateda thirty-foot-longpendulumfromthe rafters
of his barnover a graduatedcircle tracedon the dirt floor. On 1 May H. D. V. announced
his repetitionto the NewarkAdvertiserand encouragedothersto repeatthis "verysimple"
experiment.Newspapers,includingthe National Intelligencer,the Chicago Democrat,the
RichmondEnquirer, the St. Louis Intelligencer, Cummings'Evening Bulletin (Philadelphia), and the Augusta Constitutionalist,and periodicals,includingthe Spirit of the Times,
the InternationalMagazine, and the ScientificAmerican, reprintedH. D. V.'s letter. The
ScientificAmericanobservedto its sixteen thousandreaders,"Any of our farmersmay try
the experimentin their barns."14
Encouragedby H. D. V.'s example and intriguedby the press coverage, Americansof
various degrees of scientific sophisticationperformedtheir own demonstrationsof the
Foucaultpendulum.On 13 May a Washingtongentlemanvibrateda pendulumthirtyfeet
in length at his home. AlexanderC. Ross, a memberof the AmericanAssociation for the
Advancementof Science (AAAS), exhibitedthe earth'smotion for citizens of Zanesville,
Ohio, attemptingto vibrate a pendulum in the plane of its own shadow to determine
whether"it will follow the shadow as long as it continuesto vibrate."At the Paul Revere
House, a fashionable Boston hotel, an unidentifiedperson exhibited the earth's rotation.
In Trenton,Samuel D. Ingham,a businessmanand formertreasurysecretary,successfully
performedthe experimentin the rotundaof the New Jersey statehouse.'5
Although most practitionersand researcherswere slow to appreciatethe popularappeal
of the Foucaultpendulumin May, several performedpublic demonstrationsof the experiment. George R. Perkins, a professor at the Albany Normal School, performedthe experimentat the Albany Institute.Both the Albany Argus and the Albany Journal agreed
that the experimentwas beautiful.Eben N. Horsfordand William C. Bond independently
demonstratedthe experimentfor the public in Cambridgeand reportedtheirresults to the
Boston Evening Traveller.Horsford,directorof the LawrenceScientific School of Harvard
College, vibrateda thirty-six-footpendulumin his laboratory,attracting"somehundreds"
13 Boston Evening Traveller,2 May 1851, p. 2; Boston Morning Commonwealth,7 May 1851, p. 2; Boston
Evening Transcript,28 May 1851, p. 1; National Intelligencer (Washington,D.C.), 22 Apr. 1851, p. 2, 23 Apr.
1851, p. 2, 26 Apr. 1851, p. 2; and WashingtonRepublic, 1 May 1851, p. 3.
14 NewarkAdvertiser,3 May 1851, p. 2; National Intelligencer, 6 May 1851, p. 3; Chicago Democrat, 2 June
1851, p. 3; RichmondEnquirer, 9 May 1851, p. 1; St. Louis Intelligencer, 14 May 1851, p. 2; Cummings'
EveningBulletin, 5 May 1851, p. 1;Augusta Constitutionalist,29 May 1851, p. 2; Spiritof the Times:A Chronicle
of the Turf,Agriculture,Field Sports, Literature,and the Stage, 1851, 21:149; Int. Mag. Lit., Art., Sci., 1851,
3:296-297, on p. 296; and Sci. Amer., 1851, 6:289.
15 WashingtonRepublic, 14 May 1851, p. 2; National Intelligencer, 2 June 1851, p. 3; Boston Evening Transcript, 31 May 1851, p. 2; and TrentonState Gazette,29 May 1851, p. 2.
MICHAELF. CONLIN
189
of spectatorsover ten days. After repeatingthe experimentat the HarvardCollege Observatory, Bond, directorof the observatory,notified the Evening Travellerthat he had set
up a pendulumone hundredfeet long at a ship house in the CharlestownNavy Yard.16
Intriguedby Foucault'sperformanceat the Pantheonand by Bond and Horsford'slocal
demonstrations,the Massachusetts CharitableMechanics Association decided that the
Bunker Hill Monumentin Charlestownwas the ideal place for the Cambridgescientists
to repeatthe experiment.The associationprovidedfunds for the apparatus,enlisted Bond
and Horsfordto exhibit the experiment,and applied to the directorsof the Bunker Hill
MonumentAssociation to use the monumentfor that purpose. On 15 May the directors
agreedto allow HorsfordandBond to conducta repetitionin the stairwellof the monument.
Learning of preparationsfor a demonstrationat Bunker Hill, the people of Providence
clamored for their own demonstration.Bowing to popular demand,William A. Norton,
professor of naturalphilosophy, and Alexis Caswell, professor of astronomy, both at
Brown University, vibrated a pendulum ninety-seven feet in length at the Providence
railroaddepot. On 27 May Daniel Kirkwood, principal of the Pottsville (Pennsylvania)
Academy, vibrated a pendulum eighty feet in length in the car house of the Reading
Railroadat Schuylkill Haven, Pennsylvania.Intendedfor students,the exhibitionattracted
"a number of ladies and gentlemen,"who were "very attentive, and manifested a deep
interestin the subject."Pleased that Kirkwoodhad exhibitedthe experimentin Schuylkill
Haven before Bond and Horsfordhad done so at Bunker Hill, the correspondentfor the
Miners' Journal incorrectlyassertedthatthis was the first Americandemonstrationof the
Foucaultpendulum.Adding to this error,he reportedthatKirkwood'spendulumat Schuylkill Haven was twice the length of the one used by Foucaultin the Pantheon.Yielding to
populardemand,Kirkwoodalso performedthe experimentwith a shorterpendulumat the
Pottsville courthouse. Reflecting the uneven ascent of pendulum mania, the Pittsburgh
press ignored the experimentconductedby John Locke, a professor at the Ohio Medical
College in Cincinnati,with a one-hundred-footpendulumin the rotundaof the Pittsburgh
courthouse.17
On 31 May Horsford and Bond vibrated a pendulum 211 feet in length-nine feet
shorterthan the one vibratedby Foucault at the Pantheon-before the directorsof the
Bunker Hill Monument Association, a committee of the MassachusettsCharitableMechanics Association, and several scientists. By playing to the press, Horsfordand Bond
cultivatedinterestin the Foucaultpendulum.They invited editorsof the BostonAdvertiser,
the Boston Courier,the Boston Evening Traveller,and the Boston Evening Transcriptto
attenda privatedemonstrationlater that day. The Transcriptobservedthatthe "motionof
the pendulumis beautifulin the extreme."18
In Boston, anticipationof public admissionto the exhibition at the BunkerHill Monu16
Albany Journal, 9 May 1851, p. 2; Albany Argus, 12 May 1851, p. 2; Boston Evening Traveller,5 May
1851, p. 2, 14 May 1851, p. 2; and Boston Advertiser, 19 May 1851, p. 2.
17
Boston Courier, 10 June 1851, p. 1; Boston Advertiser, 19 May 1851, p. 2; Alexis Caswell and William A.
Norton, "Stateof the Results of a Set of Observationsin Repetitionof the Foucault Experiment,"Proceedings
of the AmericanAssociationfor the Advancementof Science, 1851, 6:130-132, on p. 130; Miners' J. Pottsville
Gen. Advertiser,31 May 1851, p. 2, 14 June 1851, p. 2; and CincinnatiCommercial,27 May 1851, p. 2.
18 Boston Advertiser,31 May 1851, p. 2; Boston Courier, 31 May 1851, p. 2; Boston Evening Transcript,31
May 1851, p. 2; Boston Evening Traveller,31 May 1851, p. 2; Eben N. Horsfordto the Editorsof the Boston
Evening Traveller,26 May 1851, Eben Norton HorsfordPapers, RensselaerPolytechnic InstituteArchives and
Special Collections, Troy, New York; National Intelligencer, 2 June 1851, p. 3, 5 June 1851, p. 2; and "The
Motion of the EarthRenderedVisible," Sci. Amer. 1851, 6:280. An invitationto the inauguralvibrationof the
Foucaultpendulumat the BunkerHill Monumentis located in the Eben Norton HorsfordPapers.
190
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
ment intensifiedpendulummania. Several days before the opening of the demonstration,
two newspaperspublishedfront-pagearticles on the Foucaultpendulum.The Boston Advertiser reprintedan English translationof Foucault's report of the experiment to the
Academie. Reflecting the ambivalentrelationshipbetween American and Europeanscience-Americans respectedEuropeanscience but took every opportunityto demonstrate
Americancompetence-the Advertiserincorrectlyreportedthatthe demonstrationat Bunker Hill "will give a pendulumquite as long as thatin the Pantheon,if not longer."Copying
an illustrationof the Pantheon demonstrationfrom a French magazine, the Transcript
cobbled togetheran articledetailingthe experimentand severalAmericanexhibitionsfrom
articles in five newspapers.During June and July, hundredsof Bostonians paid a small
fee to view the pendulumat the BunkerHill Monumentthrougha glass door.19
THE PEAK OF PENDULUM MANIA
Local newspaperaccounts of the BunkerHill demonstrationsparkedinterestin the Foucault pendulumfar beyond Boston. Newspapersin Providence,Albany, New York, Newark, Pottsville, Philadelphia, Washington, Richmond, Norfolk, Augusta, Savannah,
Charleston,Mobile, Louisville, and San Francisco reprintedreports of the Bunker Hill
demonstration.In early June Bird's Eye, who wrote the "Glimpsesof Men, and Things,
and Places" column for the National Intelligencer, observed that Bostonians "havejust
got up the experimenton a grandscale, turningBunkerHill Monumentinto a stupendous
pendulum,or ratherpendulumcase."In late July Bird's Eye visited the BunkerHill Monument and was treatedto a personal demonstration."The experiment,as has alreadybeen
affirmeda thousandtimes, is a very interestingone," Bird's Eye noted, "andit would be
difficult to find a place better adaptedfor its exhibition than this." Horsfordand Bond's
success at Bunker Hill encouragedothers to conduct demonstrations.The length of the
pendulumemployed by Horsfordand Bond and the interestit generatedmade BunkerHill
the benchmarkfor Americanexhibitions of the Foucaultpendulum.20
FromJuneto July, Americansvibratedpendulumsat an astonishingrate.Led by Boston
and Providence, New England expressed greaterinterest in the Foucault pendulum-as
measuredby the numberof public demonstrationsand newspaperarticles relatingto the
experiment-than any other region of the country. Since the seventeenth century New
Englandhad led the nationin the pursuitof science. While Bostonianstrampedup Bunker
Hill, latter-dayPuritansattendeddemonstrationsof the Foucaultpendulumthroughoutthe
region. In early June an unidentifiedpersonperformedthe experimentat the United States
Armoryin Springfield,Massachusetts.The Boston Morning Commonwealthreportedthat
at a local hotel a pendulum consisting of a "bullet suspended by a hair" presented "a
satisfactoryillustration"of the experiment.On 23 June, at the requestof the Connecticut
Academy of Arts and Sciences, Chester S. Lyman, a Yale-trainedastronomerthen employed defining scientific words for Webster'sDictionary, vibrateda pendulumseventyBoston Advertiser,24 May 1851, p. 1; and Boston Evening Transcript,28 May 1851, p. 1.
ProvidenceJournal,20 May 1851, p. 2; AlbanyJournal,21 May 1851, p. 2; New YorkJournalof Commerce,
31 May 1851, p. 4; NewarkAdvertiser, 17 June 1851, p. 2; Miners' J. Pottsville Gen. Advertiser,7 June 1851,
p. 2; Cummings'Evening Bulletin, 11 June 1851, p. 1; National Intelligencer, 22 May 1851, p. 3; Richmond
Enquirer, 6 June 1851, p. 1; American Beacon and Norfolk and PortsmouthAdvertiser, 5 June 1851, p. 2;
Augusta Constitutionalist,31 May 1851, p. 2; Savannah News, 6 June 1851, p. 2; Mobile Register, 12 June
1851, p. 2; Charleston Courier,4 June 1851, p. 2; Louisville Courier, 6 June 1851, p. 2; Alta California (San
Francisco),7 July 1851, p. 2; and National Intelligencer,7 June 1851, p. 2, 30 July 1851, p. 2.
19
20
MICHAELF. CONLIN
191
one feet long from the dome of the statehousein New Haven. Denison Olmsted,professor
of naturalphilosophy and astronomyat Yale College, took his class to witness the demonstration.Olmsted and Lyman explained the principles of the experimentto the "large
audience"that gathered"actuallyto see the motion of the Earth."'21
New England and the mid-Atlanticstates led the nation in the pursuit of science, as
measured by the birthplace of scientists, number of resident scientists, and number of
AAAS members. But if Washingtonis included in the South, that region demonstrated
greaterinterest in the Foucaultpendulumthan any except New England.Confirmingthe
devotion to physical science in the antebellum South found by historians, southerners
attendeddemonstrationsof the Foucaultpendulumin the city of Washingtonas well as in
South Carolina,Alabama,and Georgia.Reflectingthe uneven ascent of pendulummania,
New Orleans, the most populous and cosmopolitan city in the South, hosted no public
demonstrations.22
Despite being the center of federal government,Washingtonremaineda southerncity.
The city was second only to Boston in the numberof public demonstrationsof the Foucault
pendulumand newspaperarticles on the experiment.In June two public demonstrations
were performedin Washingtonby local practitioners.From 6 to 11 June J. Homer Lane,
an examinerin the PatentOffice, vibrateda forty-five-footpendulumbefore appreciative
crowds at the National Gallery. On 9 June CaptainCharlesWilkes, the renowned naval
explorer,vibrateda pendulum 116 feet in length under the dome of the Capitol. Wilkes
performed the demonstrationon Sunday, the only day the Capitol could be sealed to
prevent perturbingair currents.Many ladies and gentlemen observed Wilkes's exercise.
The Washingtoncorrespondentof the CharlestonCourierobservedthatthe Foucaultpendulum "seems to have thrownall our savans into extacies [sic]. Every newspaperis filled
with accounts of successful repetitionsof the experimentor with suggestions in regardto
it."923
During June, three separatedemonstrationsof the Foucaultpendulumwere performed
in South Carolina.J. A. Young, a memberof the AAAS and a meteorologicalobserverof
the SmithsonianInstitution,conducted "the French experiment"at his home in Camden
with a ten-foot pendulumand under the steeple of the town hall with a pendulumfortytwo feet in lengthbefore an appreciativecrowd. Young reportedto JosephHenry,secretary
of the SmithsonianInstitution,that he obtained the "expectedresults."Matthew J. Williams, professor of mathematicsat South CarolinaCollege, repeatedthe experimentwith
a twenty-foot pendulum in the college chapel before faculty, students, and residents of
Columbia.RobertC. Gilchristconductedthe experimentat the CircularChurchof Charleston with a pendulumfifty-two feet long, to the satisfactionof numerousspectators.24
21
RobertV. Bruce, The Launchingof ModernAmericanScience, 1846-1876 (New York: Knopf, 1987), pp.
32-39, 43-45; Bruce, "StatisticalProfile of AmericanScientists"(cit. n. 2), p. 68; Kohlstedt,Formationof the
AmericanScientificCommunity(cit. n. 2), pp. 200, 209-210; SpringfieldRepublican,10 June 1851, p. 2; Boston
Morning Commonwealth,17 June 1851, p. 1; New Haven Palladium, 24 June 1851, p. 2; and Yale Literary
Magazine, 1851, 16:327.
22 Ronald L. Numbers and Janet S. Numbers,"Science in the Old South,"Journal of SouthernHistory, 1982,
48:163-184, on pp. 167-169, 175, 184. Bruce, "StatisticalProfile of American Scientists," pp. 74, 80, and
Kohlstedt,Formationof the AmericanScientificCommunity,p. 200, place Washington,D.C., in the mid-Atlantic
region.
23 WashingtonRepublic,7 June 1851, p. 3, 11 June 1851, p. 3; TrentonState Gazette, 11 June 1851, p. 2; and
CharlestonCourier,3 June 1851, p. 2.
24 Charleston Courier, 30 May 1851, p. 1; J. A. Young to Joseph Henry, 10 June 1851, Weather Bureau,
Meteorological Correspondenceof the SmithsonianInstitution1847-67, Record Group27, National Archives,
Washington,D.C.; and CharlestonCourier, 17 June 1851, p. 2, 28 June 1851, p. 2.
192
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
In Tuscaloosa, Alabama, FrederickA. P. Barnard,professor of chemistry and natural
philosophy at the University of Alabama, and J. N. Jennings,principalof a local female
seminary,vibrateda pendulumninety feet in length underthe dome of the statehouse.The
Mobile Register took pride in the mistakennotion thatBarnardandJenningsdemonstrated
the earth's rotationwith a longer pendulumthan that employed at BunkerHill. The correspondentof the TuscaloosaObserverreportedthatJenningswould repeatthe experiment
on request "for the gratificationof the curious."In Penfield, Georgia, Joseph E. Willet,
professor of naturalphilosophy at Mercer University, performedthe experimentfor students and faculty of the largest Baptist college in the United States and for residents of
Penfield.25
Residents of the mid-Atlanticstates expressed less interest in the Foucault pendulum
than those of New England or the South. Although not producing as many scientists as
New England, the mid-Atlantic states employed more scientists and had more AAAS
membersthan any other region of the country.The surprisinglack of pendulummaniain
the mid-Atlanticstates was due largely to apathyin PhiladelphiaandNew York City. Like
fads and epidemics, pendulummania was localized, bypassing some places. No one in
Philadelphiamade a public demonstrationof the Foucaultpendulumor reportedthe results
of a privaterepetition.The AmericanPhilosophicalSociety ignored the Foucaultpendulum. Although once the leading scientific organizationin the United States, the society
had graduallylost interest in the physical sciences. By the 1840s it was largely devoted
to the ethnology of the AmericanIndian.Taking up the slack, the FranklinInstitutepublished an English translationof Foucault's announcementof the experimentto the Academie as partof the "usefulknowledge"it diffused to its members.At the FranklinInstitute's request Charles J. Allen, a schoolteacher,prepareda trigonometricdemonstration
explaining the experiment.Apparentlyunawareof Allen's account,J. S. Brown, a Washington resident, offered a similar exposition. New York City witnessed only two private
demonstrationsof the Foucault pendulum.At the urging of William A. Norton and the
editors of the Literary World,Elias Loomis, professor of astronomyat New York University, vibrateda pendulumabout eight feet in length at the university. To satisfy their
"curiosityto witness an illustrationof the rotarymotion of the Earth,"compositorsin the
printingshop of Joseph T. Cromwell repeatedthe experimentin their office with a pendulum twelve feet long that had a section of stove pipe for a bob.26
New Jerseyled the mid-Atlanticregion in interestin the Foucaultpendulum,with lively
newspapercoverage and several demonstrationsof the experiment.Editors of the state's
leading newspapers,the Newark Advertiser and the TrentonState Gazette, debated the
principles of the Foucault pendulum.Editors of the Advertiserexplained that the period
of the pendulum's apparentprecession varied accordingto the latitudewhere the experi25 Mobile Register, 18 June 1851, p. 2; and John L. Dagg, "Demonstrationof the Theory of the Pendulum
Experiment,"Amer. J. Sci., 2nd Ser., 1855, 19:280-281, on p. 280.
26 Bruce, "StatisticalProfile of American Scientists" (cit. n. 2), p. 68; Kohlstedt,Formation of the American
Scientific Community(cit. n. 2), pp. 200, 209-210; Bruce, Launchingof ModernAmericanScience (cit. n. 21),
pp. 45-47; Bruce Sinclair, Philadelphia's Philosopher Mechanics: A History of the Franklin Institute,18241865 (Baltimore:Johns Hopkins Univ. Press, 1974), pp. 136, 153; L6on Foucault, "PhysicalDemonstrationof
the Rotation of the Earthby Means of the Pendulum,"Journal of the Franklin Institute, 1851, 51:350-353;
CharlesJ. Allen, "Investigationof Foucault's Experiment,"ibid., 1851, 52:38-42; J. S. Brown, "Expositionof
Foucault'sPendulum,"ibid., pp. 352-355; Elias Loomis, "Notice of the New Experimentfor Demonstratingthe
Rotationof the Earth,"Literary World:A Journal of Americanand Foreign Literature,Science, and Art, 1851,
8:509-5 10, on p. 509; William A. Norton to Elias Loomis, 24 June 1851, Elias Loomis Papers,Beinecke Rare
Book and ManuscriptLibrary,Yale University, New Haven, Connecticut;and New-YorkTribune,2 July 1851,
p. 5.
MICHAELF. CONLIN
193
ment was performed.Unfortunately,the Advertiserreportdid not satisfy the State Gazette.
The latterwonderedhow the pendulumescaped the influenceof the earth'srotationwhen
"much lighter substances,the leaves on the trees, gossamer's web, smoke, steam, or the
featherycloud, or the rarehigher strataof the atmosphere"did not. Although unawareof
an unsuccessful demonstration,editors of the State Gazette did not understandhow the
experimentillustratedthe earth's rotation. "The difficulty is felt," they observed, "by a
good many persons besides ourselves."Despite additionalattempts,the Advertisercould
not explain the experiment to their rival's satisfaction. On 7 June Robert L. Cooke, a
memberof the AAAS, presentedthe results of his repetitionat the Presbyterianchurchin
Bloomfield to the Essex County Teachers' Association. On 21 June Theodore Strong,
professor of mathematicsat RutgersCollege, devised a "moresimple way" to exhibit the
earth'srotationthan vibratinga long pendulumwith a massive bob. Strongreportedto the
Advertiserthathe had vibrateda metal cylinderfrom a long threadand achieved the same
result as the Foucaultpendulum.27
In Newark C. Dowden, a correspondentof the AAAS, conductedan unsuccessfulrepetition in July. In an article for Appletons' Mechanics' and Engineers' Journal, Dowden
explained that scientists had "jumpedto a hasty and prematureconclusion" in asserting
that a vibratingpendulumcould provide a visible proof of the earth'srotationbecause of
two "unjustifiable"assumptions:that friction at the point of suspension was nothing and
thatthe pendulumcould vibrateindependentlyof the earth'smotion. Dr. William Kitchell,
a memberof the AAAS, andtwo othergentlemenrepeatedthe experimentwith a pendulum
thirtyfeet in length at the New Jersey Art-UnionGalleryin Newark.After numeroustrials
made over several days, they reportedto the NewarkAdvertiserthat the result was "invariably ELLIPTICALMOTION!" While it might have been theoretically possible to take
sufficient precautionsto repeatthe experimentsuccessfully, they "reluctantly"concluded
that airresistanceand the impossibilityof bringingthe pendulumcompletely to rest before
startingwere "insuperableobstacles to its practicalperformance."After consultationwith
Dowden, Kitchell reasonedthat Foucault's demonstrationat the Pantheonand subsequent
American exhibitions must have been "vitiated"by "unobservederrors."They boldly
proposedanothermethodto demonstratethe earth'smotion with a pendulumby measuring
the deviance between the calculatedmotion and the observedmotion of the apsides of the
ellipse. They hoped that Strong would determinethe angularmotion of the ellipse of a
given pendulumso that they might performthe experiment.Assuring them that the Foucault pendulumdemonstratedthe earth'srotation,Strongoffered to repeatthe experiment
for doubters.Dowden remainedunconvinced, believing that he had a "positive duty"to
reject the Foucaultpendulumbecause its "advocatescannot agree among themselves,"its
proofs were "impossible,"and its workings "absolutelyabsurd."28
Westerners expressed less interest in the Foucault pendulum than inhabitantsof the
other regions of the United States. With few cities, a short traditionof science, and a
mobile population,the West lagged behind the South in the numberof scientistsproduced
and employed. Cincinnatiled the West in science with three societies: the WesternAcademy of NaturalSciences, the CincinnatiAstronomicalSociety, and the Ohio Mechanics
27
Newark Advertiser, 21 May 1851, p. 2; TrentonState Gazette, 27 May 1851, p. 2, 29 May 1851, p. 2;
NewarkAdvertiser,4 June 1851, p. 2; TrentonState Gazette,6 June 1851, p. 2; and NewarkAdvertiser,9 June
1851, p. 2, 24 June 1851, p. 2.
28 C. Dowden, "Rotationof the Earth,"Appletons'Mechanics' and Engineers' Journal, 1851, 1:407-408, on
p. 407; NewarkAdvertiser,8 July 1851, p. 2, 11 July 1851, p. 2; and C. Dowden to Editor,Appleton's Mech.
Eng. J., 1851, 1:447.
194
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
Institute.In late June John Locke yielded to populardemand in Cincinnatiand vibrated
an eighty-foot pendulumat the Ohio Mechanics Institute.On 13 June Dr. John L. Smith,
a memberof the AAAS, exhibitedthe experimentat the medical instituteof the University
of Louisville. ThroughoutJuly John Wise, an aeronautand correspondentof the Smithsonian Institution,performed experiments relating to the Foucault pendulum from his
balloon above Zanesville and Columbus,Ohio. Wise observedthatoblong pieces of paper,
an empty pint bottle, and two pieces of board droppedfrom the balloon at an altitudeof
one mile all "spunon theiraxes."Wise reportedto newspapersandthe ScientificAmerican
thatthese objects partookof the same "rotaryand gyratorymotion"that gave the Foucault
pendulum's"variationwith a given line."29
The efflorescence of popular demonstrationsby cultivatorsin the United States was
stimulatedby the public, newspapereditors, scientists, and the demonstrators'own desire
to witness the earth's rotationor to participatein a scientific controversy.Not wantingto
be left out of the excitement of pendulummania, people in cities that had not enjoyed a
public exhibition of the Foucault pendulumcalled for demonstrations.Even though the
experimenthad been confirmedmany times before, a correspondentof the Tuscaloosa
Observernoted that "everyperson finds it gratifyingto be able to verify so remarkablea
phenomenonwith his own eyes." In Boston, Providence, Pottsville, Columbia, and Cincinnati, demonstratorsyielded to populardemand for public exhibitions of the Foucault
pendulum,and other public demonstrationswere probablydue in part to such pressure.
Newspaper editors were well placed to make such requests. The St. Louis Intelligencer
pleaded for a "philosopher"to conduct the experimentin the rotundaof the courthouseto
satisfy the curiosity of "thousandsof our citizens" and to settle the dispute over the Foucault pendulum.The New-YorkTribunerecommendedthat the experimentbe conducted
on a "properlygraduatedclock dial" to "makeold motherearthmarkher own time" and
to "tell the flight of time with an exactness hithertounparalleled."Apparentlyboth calls
went unanswered.30
Newspaper editors also encouragedcultivatorsto performdemonstrationsof the Foucault pendulumby noting the simplicity and beauty of the experimentand recommending
its repetition.The WashingtonRepublicnoted thatthe "experimentcan be triedat a trifling
outlay, and is certainly one of interest."The Albany Argus observed that the Foucault
pendulumhad the "meritof being simple, and easily got up." The Boston Evening Transcriptnotedthatthe "experimentmay be easily testedin privatehouses as it is very simple."
The SpringfieldRepublicanexclaimed thatthe "experimentis so simple, the developments
in its operationso wonderful, and the demonstrationso beautiful, that the mind must be
dull indeed that is not deeply interestedin it." A correspondentof the New YorkHerald
observed that the "experimentcan be performedby any person, down the opening of a
circularstaircasein a dwelling house or other building."Not all editors encouragedcultivators to conduct their own demonstrations.Despite the apparentsimplicity of the experiment,the InternationalMagazine cautionedthat "it should be attemptedonly by sci29
Bruce, Launchingof ModernAmericanScience (cit. n. 21), pp. 54-56; Bruce, "StatisticalProfile of American Scientists" (cit. n. 2), p. 68; Henry D. Shapiro,"The Western Academy of NaturalSciences of Cincinnati
and the Structureof Science in the Ohio Valley, 1810-1850," in Pursuit of Knowledge,ed. Oleson and Brown
(cit. n. 2), p. 238; CincinnatiCommercial,25 June 1851, p. 2; Louisville Journal, 17 June 1851, p. 2, 26 June
1851, p. 2; Scioto Gazette, 7 July 1851, p. 3, 19 Aug. 1851, p. 2; Sci. Amer., 1851, 6:312; and John Wise,
Throughthe Air: A Narrativeof Forty Years'Experienceas an Aeronaut (Philadelphia,1873), p. 420.
30 Mobile Register, 18 June 1851, p. 2; St. Louis Intelligencer, 6 June 1851, p. 2; and New-YorkTribune,14
July 1851, p. 4.
MICHAELF. CONLIN
195
entific men,"and it reprintedJosephJ. Sylvester's admonitionin the LondonTimesagainst
demonstrationsby laypersons.3'
Some researchersand practitionersencouragedcultivatorsto performthe Foucaultpendulum experiment.Horsfordinformed the Boston Evening Traveller's readersthat "this
beautifulexperimentis so simple thatit may be readilyrepeatedin most of our dwellings,"
as it requiredonly a screw, a small weight, and a slender metal wire. Locke gave several
tips to the readers of the Cincinnati Commercialwho hoped to repeat the experiment,
detailing the mode of suspension, the shape of the bob, and the type of wire. To allay
concerns that a suitablependulummust be made on a grandscale, Locke reportedthathe
had "succeededperfectly"in performingthe experimentwith shortpendulums,including
one only thirty-nineinches long. Lewis R. Gibbes, professorof astronomyat the College
of Charleston,told interestedpersons not to be discouragedfrom performingthe experiment for want of a properpendulum."Any heavy body suspended,free from friction,with
a rod projectingfrom it horizontally,will indicate the motion as truly as a pendulum,"he
explained, though it "wouldbe more liable to disturbancefrom extraneouscauses."32
Not all demonstratorsencouragedcultivatorsto performthe experiment.Quoting Sylvester's warningin the London Times,JohnL. Smith assertedthat supposingthe Foucault
pendulumto be a "popular"experimentwas an "egregiouserror."Smith observedthatthe
Foucaultpendulumdemonstrationwas "notso easily understoodor so readilyperformed"
as many newspaperaccounts suggested. Elias Loomis warnedthe readersof the Literary
Worldthat the "difficultiesin the way of subjectingthese results to the test of experiment
are very serious."Avoiding air currentsand making sure the pendulumwas at rest before
beginning the experimentwere crucial for success. To avoid these "evils," Loomis observed thatexperimentersemployed bobs as heavy and wires as long as possible and cited
approvinglythe dimensions of the pendulumsvibrated at the Pantheon and the Bunker
Hill Monument.Loomis cautioned that the slightest lateral impulse-even "a breathof
air"-could cause elliptical oscillations and "vitiate"the experiment.33
THE CONFUSION OF PENDULUM MANIA
Tens of thousandsof Americansread accounts of the Foucaultpendulumand thousands
attendeddemonstrationsof the experiment,but many did not understandhow it showed
the earth'srotation.The experimentprovokedreactionsrangingfrom admirationto incredulity to scorn. The Boston Morning Commonwealthidentified the two questions raised
by the Foucaultpendulumthat vexed the popularmind. Many Americanswonderedhow
the pendulumoscillated independentlyof the earth's rotationif its point of suspensionwas
attachedto the earth.Expecting the earthto returnto the pendulum'splane of oscillation
in twenty-fourhours,most Americanswere confoundedwhen they learnedthatat latitudes
in the United States this process took over thirty-fourhours. Even as they reprintedaccounts of demonstrationsof the Foucaultpendulum,editors of several newspapers-the
ProvidenceJournal,the TrentonState Gazette,the Scioto Gazette,andthe Friends' Weekly
Intelligencer-confessed that they did not understandthe experiment.Their readersdid
31 WashingtonRepublic, 14 May 1851, p. 2; Albany Argus, 12 May 1851, p. 2; Boston Evening Transcript,
31 May 1851, p. 2; SpringfieldRepublican, 10 June 1851, p. 2; New YorkHerald, 13 June 1851, p. 3; and Int.
Mag. Lit., Art., Sci. 1851, 3:296-297, on p. 296.
32 Boston Evening Traveller,5 May 1851, p. 2; CincinnatiCommercial,27 May 1851, p. 2; and Picayune, 16
June 1851, p. 3.
33 Louisville Journal, 17 June 1851, p. 2; and Loomis, "Notice of the New Experiment"(cit. n. 26), p. 510.
196
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
not understandit either. Many Americans wrote to newspapers seeking an intelligible
explanation.Having read everything available on the Foucaultpendulum,A. Z., a correspondentto the National Intelligencer,confessed, the "moreI read the less I understand."
As the Foucaultpendulumhad given A. Z. many sleepless nights, he hoped thata scientist
would explain the experimentin a "manneradaptedto the understandingsof those who
... have more zeal for science than capacity for imbibing it."34
Severalresearchersandpractitionersrespondedto A. Z.'s call and similarrequestsmade
by others. Horsfordwrote an explanationof the Foucaultpendulumfor the editors of the
Boston Evening Traveller,the National Intelligencer, the ScientificAmerican,the American Railroad Journal, and Appletons' Mechanics' and Engineers' Journal. Caswell and
Norton each wrote detailed explanationsof the experimentfor the Providence Journal.
Lane wrote an explanationof the experimentfor the NationalIntelligencer.Locke provided
an explanationof the Foucault pendulumfor "plainpracticalmen" on the front page of
the CincinnatiCommercial.At the urging of Norton and the editorsof the LiteraryWorld,
Loomis too wrote an explanationof the experiment.35
Cultivatorsand others also offered explanationsof the Foucaultpendulum.Perhapsthe
most interestingexchange took place in Providence.The explanationmade by W. for the
Providence Journal, which included awarenessof the perturbingeffects of air resistance
and friction at the point of suspension,won praise from Caswell, who called the writeran
"ingeniousscientific friend."Not all cultivatorswere so clever. Admittingno expertisein
science, F. could not reconcile the twenty-four-hourrotationof the earthwith the thirtyfive-hourapparentprecessionof the pendulum'splane of oscillationat Providence.Despite
making no pretensions"to controvertthe calculationsand conclusions of learnedprofessors," F. offered a theory of his own: the pendulumpartook of the earth's rotation and
completed a revolution every twenty-fourhours. Proposing that scientists were "a little
too fast in their calculations,"he called for experimentsto be continueduntil a complete
revolution of the pendulum'splane of oscillation was achieved. Despite several explanations publishedin the Providence Journal, F. remainedunpersuaded,contendingthat scientists had "beenegregiously humbuggedwith a scientific nonentity."After F. challenged
"any learnedman in the world"to show by theory or experimentthat a pendulumcould
oscillate independentlyof the earth's rotation,several accepted. One correspondentconceded that most of the explanationsof the experimentprintedin the Providence Journal
containedtoo many "sines,cosines, tangents,andA.B.C.'s" to be interestingfor the general
readerbut accepted the experimentas valid because of Airy's endorsement.Anotherexplained that the Foucault pendulumcapped the Scientific Revolution, exhorting that everyone who gave the matter some thought must exclaim, like Galileo, "Yes, the earth
turns !"36
Unconvinced by these explanationsand aware of scientific hoaxes perpetratedby charlatans,several newspapereditorsrejectedthe Foucaultpendulumas a fraud.After "patient
study,"the editors of the Providence Post rejected the experimentas "nonsense."Citing
34 Boston Morning Commonwealth,5 June 1851, p 1; Providence Journal, 21 May 1851, p. 2; TrentonState
Gazette, 27 May 1851, p. 2; Scioto Gazette, 2 June 1851, p. 2; Friends' WeeklyIntelligencer, 1851, 8:75; and
National Intelligencer, 30 May 1851, p. 2.
35 Boston Evening Transcript,6 June 1851, p. 2; Sci. Amer., 1851, 6:312; AmericanRailroad Journal, 1851,
24:355; Appletons'Mech. Mag. Eng. J. 1851, 1:406-407; ProvidenceJournal, 24 May 1851, p. 2, 28 May 1851,
p. 2; National Intelligencer, 30 May 1851, p. 2; Cincinnati Commercial,8 June 1851, p. 1; Norton to Loomis,
24 June 1851, Elias Loomis Papers;and Loomis, "Notice of the New Experiment"(cit. n. 26), p. 509.
36 ProvidenceJournal, 21 May 1851, p. 2, 28 May 1851, p. 2, 12 July 1851, p. 2, 28 Aug. 1851, p. 2, 29 Aug.
1851, p. 2, 6 Sept. 1851, pp. 1-2.
MICHAELF. CONLIN
197
no sources, they assertedthat the pendulumfollowed the magnetic meridianand "is undoubtedlyjust aboutas much a demonstrationof the rotationof the earth,as may be found
in the binnacle of any vessel in our harbor."The CharlestonMercurytook no notice of
the Foucaultpendulumexcept to reprintan unidentifiedScottish experimenter'sassertion
that the experiment did not work because the pendulum followed the earth's magnetic
meridian.The New YorkHerald, the SavannahDaily News, and the Providence Journal
reprintedPunch's method of affirmingthe earth's rotationwith liberal doses of brandy.37
The Louisville Democrat borrowed Punch's joke to ridicule its rival, the Louisville
Journal, which endorsed the Foucault pendulum.The two newspapersincorporatedthe
experimentinto partisanpolitical dispute. In a series of fourteeneditorials,the Democrat
lampooned its Whiggish opponent for having been duped by the "pendulumhoax," and
the Journal defended itself by adducingnames of scientists who had repeatedthe experiment. Observingthatthe earthwas "noLocofoco editorto be ashamedof hermovements,"
the Journal noted that the earthproudly demonstratedits movement to the Foucaultpendulum. The papercalled upon John L. Smith, who had performeda recent demonstration,
to settle the matter. Unconvinced by the explanation made by Smith or by doctors of
medicine, theology, or chemistry, the Democrat would only accept the verdict of a true
authoritysuch as Pierre Simon Laplace. Adducing the supportof Joseph J. Sylvester and
William C. Bond, the Journal observed that "if we are not to take the opinion of doctors
in medicine, of lawyers in law, and of philosophersin mattersof philosophy,"then every
man would be "his own doctor, lawyer, and philosopher"-with disastrousresults.38
Just as Americans throngedto see Albert Einstein in 1921 even though they did not
understandhis theories of relativity, they were enthralledby the Foucault pendulumin
1851 even though they did not understandhow it revealed the earth'srotation."Notwithstandingthe many explanationsof the Frenchexperimentwhich rendersvisible the rotation
of the globe on its axis," the Albany Argus observed, "thereis a good deal of misapprehension"regardingthe "modusoperandiand the theory of it." Newspapercoverage of the
Foucaultpendulumcontributedto the confusion that surroundedthe experiment.In their
haste to encouragereadersto performtheir own demonstrationsand to give a forum for
explanationsof the experiment,editors circulatederroneous and unintelligible accounts
through the common practice of reprintingreports from other newspapers.Even when
scientists providednewspaperswith accurateaccounts, errorsappeared.Sending Loomis
a newspaperarticle on the BunkerHill demonstration,Horsfordnoted that "in general it
is correct"and will need only a "few particulars"to satisfy a scientist.39
Not all scientistsfoundthe press so obliging. Yielding to populardemandthatan account
of his demonstrationin Columbia, South Carolina,be published, Matthew S. Williams
prepareda "neatdistinctly writtenmanuscriptfor each of the town papers."Althoughthe
experimentwas not performedunderperfectconditions,Williamsinformedone newspaper
that the "resultwas too striking to fail in convincing the most skeptical"of the earth's
rotation,except the "incurablyignorantor insanely skeptical."Two newspaperspublished
Williams's account accurately;another"made only inconsiderableerrors,the sense was
37 Providence Post, 7 June 1851, p. 2; CharlestonMercury, 10 June 1851, p. 2; New YorkHerald, 13 June
1851, p. 3; Providence Journal, 30 May 1851, p. 1; and SavannahNews, 9 June 1851, p. 2.
38 Louisville Democrat, 14 June 1851, p. 2; Louisville Journal, 12 June 1851, p. 2, 16 June 1851, p. 2, 17
June 1851, p. 2; LouisvilleDemocrat, 20 June 1851, p. 3; and Louisville Journal, 26 June 1851, p. 2.
39Albany Argus, 7 June 1851, p. 2; Allan R. Pred, Urban Growth and the Circulationof Information:The
United States System of Cities, 1790-1840 (Cambridge,Mass.: HarvardUniv. Press, 1973), pp. 57-58; and
Horsfordto Loomis, 9 June 1851, Elias Loomis Papers.
198
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
preserved";but the South-Carolinian,"to whom I had given the plainest copy, made sheer
nonsense"of it. After the editor of the South-CarolinianignoredWilliams's pleas to publish a correction,the poor scientist feared for his reputation.
Every paperI have seen in SC, many of the papersin Georgia, especially the Savannahpapers
and at least one paper of the North, how many more I know not, have republishedthis little
communicationof mine and in every instance the copy has been made from the Carolinian.
Out of so many papers,falling into the handsof so many differentpersonsit will not be thought
too great a stretchof vanity to suppose some few men of sense and science may have read my
article[.] And what DO they think? A grammaticalmistake might be overlooked in a Mathematician, deficiency of taste would not perhapsbe rigidly & severely criticized; but who so
indulgentas to overlook sheer nonsense?40
Williams's difficulties reflected the tension between accuracy and accessibility that researchersand practitionersfaced when relying on newspapersto popularizephysical science.
American religious spokesmen also participatedin the pendulummania. Ratherthan
extolling the Foucaultpendulumas proof of divine law, Methodist,Presbyterian,Baptist,
and Universalistjournals followed the secular press in marveling at the experiment.As
antebellumAmericans had reconciled science with theology, religious figures probably
agreed with the editors of the Boston Morning Commonwealthwho recommendedthe
study of the Foucaultpendulumas an insight into the Creator'sworks because "thereis
nothingbetteradaptedto enlargethe mindsof the people."Althoughseveraldemonstrators
had religious training-for example, James Curley, a Catholic priest; ChesterLyman, a
Congregationalminister;and Alexis Caswell, a Baptistminister-and at least threepublic
exhibitions were made on church grounds, no record of such an exhortationhas been
found. Americans approvinglyalluded to Galileo's defiantwhisper that the earthmoved,
but no one made religious objections to the demonstrationof the earth's rotationwith a
Foucault pendulum. Instead, churchmenparticipatedin the scientific controversy. The
ReverendJohn L. Dagg, a leading Baptist theologian and presidentof MercerUniversity,
presented a geometric proof of the Foucault pendulum. Maintainingthat the pendulum
moved with the earthand oscillated in a series of intersectingplanes, the ReverendS. B.
Goodenow disputed the results of Robert L. Cooke's demonstrationat a Presbyterian
church in Bloomfield, New Jersey, on scientific, not religious, grounds.Enoch Lewis, a
PhiladelphiaQuakerwho editedFriends' Review,rejectedthe Foucaultpendulumbecause
it was "not explicable upon the principles of mechanicalforce." Objectingto Gould and
Horsford'sexplanationsof the experimentin the Boston Evening Travelleron "mechanical" grounds,ThomasHill, a Congregationalministerfrom Waltham,Massachusetts,and
a member of the AAAS, asserted that "no free pendulumcan be swung in common air
and be confined to a mathematicalplane."After viewing the BunkerHill demonstration,
Hill noted that Horsford's "greatcare and skill" mitigatedthis difficulty.4'
40 CharlestonCourier, 17 June 1851, p. 2; and MatthewS. Williams to James HenryThornwell, 14 July 1851,
James Henry ThornwellPapers,South CarolinianaLibrary,University of South CarolinaArchives, Columbia.
41 Zion's Herald and WesleyanJournal, 1851, 22:115; ChristianObserver,1851, 30:100; ChristianWatchman
Reflector,1851, 32:80; TrumpetUniversalistMag., 1851, 23:208; RonaldL. Numbers,Creationby NaturalLaw:
Laplace's Nebular Hypothesis in American Thought(Seattle: Univ. WashingtonPress, 1977), pp. 25-27, 6365; Boston Morning Commonwealth,5 June 1851, p. 1; Dagg, "Demonstrationof the Theory of the Pendulum
Experiment"(cit. n. 25), p. 280; NewarkAdvertiser,9 June 1851, p. 2; Friends' Review:A Religious, Literary,
and MiscellaneousJournal, 1851, 4:569-573, on pp. 570, 572-573; and Boston Evening Traveller,7 May 1851,
p. 2, 5 June 1851, p. 2.
MICHAELF. CONLIN
199
THE FALL OF PENDULUM MANIA
By late July pendulummaniahad waned:only one public and a few privatedemonstrations
of the Foucaultpendulumwere performedafterthis time. For the benefitof the Washington
public, Dr. J. C. Hall exhibitedthe experimentat his residence.In his laboratory,Theodore
Strong made anothervarianton the experimentby spinning a large wooden wheel with a
steel needle in its hub over a glass socket. Strong assertedthat when it was rotatedin a
room free from air currentsthe wheel precessed at the appropriaterate for its latitude.He
found that the experimentcould be successfully repeatedwith smaller wheels. Believing
that Strong's wheel was the "latest perpetualmotion [machine] we have heard of," the
New-York Tribune contended that it "puts the French pendulum mode entirely in the
shade." In a letter to Stephen Alexander, professor of astronomyat PrincetonCollege,
Joseph Henry disagreed,believing that friction would be too great for Strong's wheel to
demonstratethe earth's motion. Henry's doubts seem well founded. Although the wheel
was later exhibited at the Naval Observatory,Strong neitherpublished nor presentedan
account of his experimentfor a scientific audience.42
In late August, the annualmeeting of the AAAS in Albanyrevived the pendulummania.
In additionto local newspapers,the National Intelligencerand the New-YorkTribunesent
reportersto the meeting.The Foucaultpendulumhad "halfturnedthe headsof philosophers
for some monthspast,"Bird's Eye of the National Intelligencerobserved,and it continued
to do so. For two days discussion of the Foucault pendulum excited "generalinterest,"
with demonstratorspresentingresults and answeringquestions from the audience. Members of the AAAS -ranging from Eben Horsford,who had performedthe famous Bunker
Hill demonstration,to William Kitchell, who rejectedthe experimentafterhis repetitions
consistentlydeterioratedinto ellipticity-took a leading role in popularizationof the Foucault pendulum,performingalmost half of the identified public demonstrations.Despite
this varied participation,the AAAS took notice only of the results of demonstrations
conductedby a few practitionersand researchers-George R. Perkins,LieutenantEdward
B. Hunt of the United States Engineers,William Norton, and Horsford.43
Norton and Horsfordalone had noteworthyresults. After twenty-threetrials of the pendulum they vibrated at the Providence railroad depot, Norton and Alexis Caswell had
discoveredthatthe apparentprecessionof the pendulumtook longerthantheorypostulated,
but they resisted speculation as to the cause of this discrepancy.They believed that the
expected results could be obtained only by experimentsin a closed room with a heavy
weight and a long wire. Waiting severalweeks until the numberof spectatorsat the Bunker
Hill Monumentdiminishedbefore makingdetailedobservations,Horsforddiscoveredthat
the heat of the sun expandedthe stones of the monument,which moved the pendulum's
point of suspension. On sunny days the monumentleaned northwardabout three-fourths
of an inch. To compensate,Horsfordchangedthe point of suspensiononce or twice a day
accordingto the intensityof the sun. JosephHenryfound the discovery of the monument's
movement a "very interestingresult."The New-YorkObserveragreed, noting that "it is
wonderfulto think that the BunkerHill Monumentis bending like a bow backwardand
42
National Intelligencer, 24 July 1851, p. 3; David A. Wells, ed., Annual of ScientificDiscovery; or, YearBook of Facts in Science and Artfor 1852 (Boston, 1856), p. 158; New-YorkTribune,5 Aug. 1851, p. 7; and
Henryto StephenAlexander, 18 July 1851, JosephHenryPapers,SmithsonianInstitutionArchives,Washington,
D.C.
43AlbanyArgus, 26 Aug. 1851, p. 2; National Intelligencer, 2 Sept. 1851, p. 2; and New-YorkTribune,27
Aug. 1851, p. 6.
200
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
forwardevery day by the influence of the sun!" Although Horsfordhad informed newspapersof this finding a month earlier,it remainednewsworthy.44
Not all of those who presentedpapersat the AAAS meeting had performeddemonstrations, and not all of those who had performeddemonstrationspresentedpapers.JamesD.
Dana offered a geometric explanationof the Foucault pendulum.Unconcernedwith the
forces involved, Dana does not appearto have performedthe experiment.AlthoughRobert
L. Cooke, William Kitchell, and C. Dowden were members of the AAAS who had performed demonstrationsof the experimentand who lived near Albany, not one of these
cultivatorswas invited to present a paper. Nor was Theodore Strong, a practitionerwho
had achieved dubious results. This apparentsnub may have been a consequence of the
irregulartransmissionof reportsof exhibitions, but a more likely cause was the association's division between researchersand practitionerswho wantedto define the credentials
necessary to be taken seriously by the profession and cultivatorswho wanted to open the
organizationto all with an interest in science. Although none of the presentersdisputed
others' findings, Bird's Eye reportedthat the "result"of the deliberationswas that the
"phenomenaof the pendulum have not yet been fully mastered or clearly explained,"
suggesting that objections were raised by those demonstratorswho were not invited to
presenttheir results or by others in the audience.45
Like the AAAS, ChesterLymanignoreddemonstrationsperformedby manypractitioners and cultivators.In two articles for the AmericanJournal of Science, Lyman surveyed
Americandemonstrationsof the Foucaultpendulum,identifyingsources of errorand comparing them to Europeandemonstrations.He limited his review to his demonstrationat
New Haven, Bond and Horsford'sat BunkerHill, Loomis's at New York University, and
Caswell and Norton's at Providence.Unaware of any demonstrationsin which the oscillation of the pendulumdid not graduallydeterioratefrom a rectilinearmotion to an elliptical one, Lyman identifiedthis tendency as the greatestobstacle to conductingthe experiment successfully. Althoughan able experimentercould keep the ellipticity small, Lyman
doubted that it would be possible to "conductthe experimentso skillfully as entirely to
avoid these sources of error."Even with "theoreticallyperfect" conditionsand apparatus,
Lyman reasoned,the pendulumwould travel in a slightly elliptical motion because of the
earth's rotation.Only at the equatorwould it be possible to vibrate a pendulumwithout
any elliptical motion. Lymanblamed "imperfectionsin the apparatus,"lateralvibrationof
the pendulum"at the moment it is disengaged,"and especially air currentsfor producing
sufficientellipticity to make an unsuccessfuldemonstration.Observingthateven a "single
breath"could disrupt a demonstration,he contended that the "wonder is, not that the
experimentsexhibit some discrepancyin results, but that they show so little."46
Reviewing demonstrationsof the Foucaultpendulum,Lyman praisedFoucault's ingenuity but found American exhibitions of the experiment superiorto those performedin
Europe. (See Figure 3.) He noted that the pendulumsat Bunker Hill, at Providence, and
at New Haven were longer thanthose vibratedin Europe,except for Foucault'spendulum
44Caswell and Norton, "Observationsin Repetition of the Foucault Experiment"(cit. n. 17), pp. 130-131;
Horsford to Loomis, 9 June 1851, Elias Loomis Papers; Eben N. Horsford, "The Pendulum at Bunker-Hill
Monument,"Proc. Amer.Assoc. Advance. Sci., 1851, 6:132-137, on p. 133; Henryto Alexander, 18 July 1851,
Joseph Henry Papers;TrentonState Gazette,21 July 1851, p. 2; and New-YorkObserver, 1851, 29:245.
45 James D. Dana, "Foucault'sPendulumExperiment,"
Amer. J. Sci., 2nd Ser., 1851, 12:200-204, on p. 200;
Dana, "On the PendulumExperiment,"Proc. Amer.Assoc. Advance. Sci., 1851, 6:132; Kohlstedt,Formationof
the AmericanScientificCommunity(cit. n. 2), pp. 138-154; and National Intelligencer, 2 Sept. 1851, p. 2.
46 ChesterS. Lyman, "Observations
on the Pendulum,"Amer.J. Sci., 2nd Ser., 1851, 12:251-255, on pp. 251252; and Lyman, "Observationson the PendulumExperiment,"ibid., pp. 398-416, on pp. 399, 401-403.
201
MICHAELF. CONLIN
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at the Pantheon.Long pendulumswith heavy bobs provided more accurateresults than
shorterones with light bobs, Lyman explained, because massive bobs vibrating at low
velocity have low air resistance.Believing that Europeanexperimenterswere more interested in exhibition than in experiment,Lyman observed that they gave the pendulum"a
very wide swing" to make the precession of the plane of oscillation obvious to spectators.
Althougha long arc of oscillationwas well suitedfor "popularaudiences,"Lymanasserted
that "for the purpose of philosophical observationa smaller arc is much better"because
both air resistance and elliptical motion were diminished.Lyman neglected over twenty
Americandemonstrations,includingthose performedby JohnLocke, FrederickA. P. Barnard,CharlesWilkes, and Daniel Kirkwoodwith longer pendulumsthan his own at New
Haven. Although Lyman may not have been aware of all of these exhibitions, he surely
must have known aboutthe well-publicizeddemonstrations,such as the one at H. D. V.'s
barn.At the same time, Lyman praised an account of the experimentby James D. Dana,
a scientistwho did not performa demonstration,as the best for "mindsnot speciallytrained
for mathematicalinvestigations."Appreciatingthe popularinterestarousedby the experiment, Lyman reportedthat "manypersons, even of education, find it difficult to understand"how a vibratingpendulumdemonstratedthe earth'srotation.47
Almost as importantas those who performedpublic demonstrationsof the Foucault
pendulum were those who did not. Despite national and local interest in the Foucault
pendulum,neither OrmsbyM. Mitchel, directorof the CincinnatiObservatory,nor Matthew F. Maury,directorof the Naval Observatoryin Washington,performedpublic dem47
Lyman, "Observationson the PendulumExperiment,"pp. 399-408, 410.
202
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
onstrationsor providedpublic explanationsof the experiment.Theirreticenceis puzzling,
as these two men were among the leading popularizersof physical science in the antebellum United States and they took advantageof almost every opportunityto attractattention
to themselves and their observatories.Perhaps Mitchel and Maury found the field too
crowded with demonstrators.Bond and Horsfordhad alreadyconductedthe most famous
American exhibition at Bunker Hill, and many others had performeddemonstrationsas
well. To follow the crowd would gain neitherMitchel nor Maury special distinction.48
OtherprominentAmericanscientists,includingGeorgeP. Bond, BenjaminPeirce,Sears
C. Walker, Alexander Dallas Bache, James Curley, and Joseph Henry, did not perform
public demonstrationsof the Foucaultpendulumor make public comments on the experiment.Not wishing to be caughtup in the excitementof pendulummania,these researchers
attendedpublic demonstrations,repeated the experiment in private, discussed it among
themselves,or took no notice of it. Inspiredby his father'srepetitionat BunkerHill, George
Bond, en route to observe a solar eclipse in Norway, visited the Pantheonin June to see
the experimentand meet Foucault. Although Peirce, Perkins Professor of Astronomy at
HarvardCollege, and Walker, an astronomerin the United States Coast Survey, had precipitatedthe Neptune controversy,they shied away from pendulummania. Peirce left no
recordedreactionto the experiment.Walkerwrote a letterto an unidentifiedcorrespondent
in Cincinnati, probably his brother, explaining it. He dismissed the "many vague and
trifling articles in the newspapers on the subject of Foucault's Pendulum experiment."
Delighted by Wilkes's demonstrationat the Capitol,WalkerregardedFoucaultas "another
Galileo in this discovery" and marveled that "so simple a thing should have remained
untriedfor so long." Walker's correspondentsent the letterto the CincinnatiCommercial
to explain the experiment.Bache, superintendentof the United States Coast Survey, devised a simple methodto determinewhethera wire was sufficientlyflexible in all directions
to be used in a demonstration,which won praisefrom Lyman.The ReverendJamesCurley,
directorof the GeorgetownCollege Observatory,performedthe experimentat Georgetown
College and requestedthat Henry do so as well. Henryrepeatedthe experimentin private
at the SmithsonianInstitution.He tried to produce the "same effect" by floating a glass
disk on water but found that friction was too great. Despite the Smithsonianpolicy of
answeringscientific questions and threepublic requeststhathe "explainthe whole thing,"
Henry made no public comment on the Foucaultpendulum.49
PerhapsHenry's silence on the subject can be attributedto a desire not to encourage
pendulummania, which he ruefully observedhad "causedgreatexcitement"in the Washington area. After reading accounts of the experimentand performingrepetitionswith an
eleven-foot pendulum,Samuel Tyler, a lawyer from Frederick,Maryland,and a leading
Americanphilosopher,informedHenry that the Foucaultpendulumwas an "entiredelusion" which "in no degree indicated"the earth's rotationbecause the pendulum's oscillation always deviatedinto an ellipse. An ardentBaconian,Tyler maintainedthatFoucault
erredby consideringthe pendulum'soscillation as a "problemof rationalmechanics,"that
48
Philip S. Shoemaker,"StellarImpact:OrmsbyMacKnightMitchel and Astronomyin AntebellumAmerica"
(Ph.D. diss., Univ. Wisconsin-Madison, 1991), pp. 191, 220; and Bruce,LaunchingofModernAmericanScience
(cit. n. 21), pp. 116-117, 176-178, 181-185.
49George P. Bond, "Journal,"25 June 1851, HarvardUniversity Archives, Cambridge,Massachusetts;Cincinnati Commercial,16 June 1851, p. 2; Lyman, "Observationson the PendulumExperiment"(cit. n. 46), p.
399; National Intelligencer,29 May 1851, p. 2; James Curley, "Journalof Things Relating to the Observatory,"
11 June 1851, GeorgetownUniversity Special Collections, Washington,D.C.; Joseph Henry Locked Book, 28
June 1851, Joseph Henry Papers;and National Intelligencer,28 May 1851, p. 2.
MICHAELF. CONLIN
203
is, a mathematicalproblem, when it was really an experimentalproblem "made in the
midst of all the forces of nature."Until experimentationand deductioneliminatedall other
explanations,Tyler dismissed those based on "purelymechanicalideas."Althoughclaiming to have read accounts of the experiment,Tyler seemed unawarethat Foucault's inspiration came from experimentswith clock pendulumsratherthan from mathematicaldeduction. After receiving Tyler's letter, learning of Theodore Strong's wheel, reading
several unintelligiblearticles in the National Intelligenceron the Foucaultpendulum,and
seeing T. EgertonBrowne at the Smithsonianlibrary"almostevery aftemoon ... looking
at the pendulum,"Henry noted that "severalpersons have become derangedby studying
it." Ten days after Browne, a post office clerk, published a letter in the National Intelligencer assertingthat Foucaulthad inadvertentlydiscovered a "unitcube of mensuration,"
he died of what Henry diagnosed as "brainfever on account of the excitement."Given
Henry's dislike of charlatanismand popular science, he may have regardedpendulum
mania as unseemly or at least not comportingwith the dignity of scientists.50
CONCLUSION
Benjamin A. Gould contended that the Foucault pendulum was unique among physics
experiments:"probablynone more beautiful was ever devised; certainly few have ever
attractedequal attention from all classes of scientific men and from the public." Many
Americansagreed. Reflecting on advances since the Battle of BunkerHill, editors of the
NewarkAdvertiserpraisedthe repetitionat the monumentas a sign of a historicimprovement in world affairs. In 1851 France and the United States were allied again, not "for
purposes of violence and destruction,"as in 1775, but "in the pursuitof science and the
arts."The Bunker Hill demonstrationand the World's Fair at Paris were sure indicators
that the "good time has alreadycome; our swords have been beaten into telescopes, and
our spearsinto pendulums,andnationsshall not learnwar any more;butturntheirattention
Pendulummania showed that popularentirely to NaturalPhilosophy and Astronomy."51
ization of physical science in the antebellumUnited States was flourishing,but it divided
the American scientific community along professional and geographical lines. Tens of
thousandsof Americansreadpopularaccounts,hundreds(andperhapsthousands)attended
public repetitions,and dozens performedtheirown demonstrationsanddisputedthe physical principles of the experiment.Many cultivators,practitioners,and researcherstook an
active role in popularization,by performingpublic repetitionsand by publishingpopular
explanations of the Foucault pendulum, but only a handful-Chester Lyman, Eben N.
Horsford,William A. Norton, George R. Perkins,EdwardB. Hunt, and JamesD. Dana
were invited to present papers on the Foucault pendulum at the AAAS meeting held in
Albany. In a review for the AmericanJournal of Science, Lyman ignored a dozen demonstrationsconductedby his counterpartsin the South and West. Many researchersmissed
the uniqueopportunityto be popularizersofferedby pendulummania.Some of them, such
as JosephHenry,AlexanderDallas Bache, BenjaminPeirce, StephenAlexander,andSears
C. Walker,avoidedrepeatingor even commentingon the experimentfor the public.Others,
such as Denison Olmsted,Elias Loomis, Lewis R. Gibbes, and BenjaminA. Gould, made
50
Joseph Henry Locked Book, 28 June 1851; Samuel Tyler to Henry, 8 Aug. 1851, Joseph Henry Papers;
National Intelligencer, 13 June 1851, p. 2, 7 Aug. 1851, p. 2; and Bruce, Launchingof ModernAmericanScience
(cit. n. 21), p. 185.
51 Boston Evening Traveller,2 May 1851, p. 2; and NewarkAdvertiser, 17 June 1851, p. 2.
204
POPULARAND SCIENTIFICRECEPTIONOF THE FOUCAULTPENDULUM
only limited public explanations.Two researchers,Ormsby M. Mitchel and Matthew F.
Maury, finding the field of pendulum demonstratorstoo crowded, waited for a better
opportunityto draw attentionto themselves and their observatories.
The geographicaldistributionof interestin the Foucaultpendulum,as indicatedby the
numberof public demonstrationsand newspaperarticlesrelatingto the experiment,challenges assertionsmade by historiansabout the diffusion of scientific knowledge and the
level of scientific activity in the antebellumUnited States. No otherAmericancity had as
many newspaperarticles on the Foucault pendulumand as many public demonstrations
of the experimentas Boston and Washington, though Providence, Albany, and Trenton
were next in order.During the three months of pendulummania, five Boston newspapers
printedover fifty articles relating to the Foucaultpendulum,and two Washingtonnewspapersprintedover forty articles on the experiment.These articlesincluded accountsand
notices of local demonstrations,reprintedreportsof other Americandemonstrations,and
letters questioning or explaining the experiment. The people living in the Boston area
enjoyed five public demonstrationsof the Foucaultpendulum;the people of Washington,
four. These figures suggest that while New England led the way in the pursuitof science
and the West lagged behind, the South was not so far behind the mid-Atlanticstates as
historianshave previously asserted.