New-York daily tribune., 1851-08-27
SCIENTIFIC CONVENTION
Annual Meeting Of the American Association
for the Advance ement OF SoieDoe.
AZ ALBAs
PIETH DAY.


or the ensuing year Prof BENJAMIN PIERCE, OF
U.ua,d rniversi,y. was chosen UNANIMOUSLY he
will make q most excellent presiding officer
The ,Iace Of the mex, Annual Meeting was fixed
a, Cleveland. O. IN accordance with the invitation
of,,e Mavor and Council OF that city. The time
has mt heen determined, the locality Of the IN
termedla,c semI-annual Session Of the Association
A soirl,ed debate On Constitutional questions oc-
~u,,ed the Standing Committee being tac,y re-
oyoaehed for alleged usurpations Of preroga;ive.
The matters IN dispute, however, were satisfactorily
.xnlained and the action OF the Committee was ar
nr1ved II must frequently be necessary in conduct
,ng the vast amount Of business which accuTnuiates
mon the HANDS Of this Committee during session
OF the Association, that Their powers should take an
EXTENDED course and i the very letter OF the Con-
stitution be not always followed, there neec De no
reason for sensvcness on the part of thin skinned
people who may not be treated with the distinction
that would be awarded them in times OF less coniu-
son.
The Convention divided to-day into four Sections,
VIZ: Mathematics and Physics, Zoology, Geology,
and Chemistry and Mneralogy. The number OF
papers on the Register cannot be less than one hun
dred and fifty, although many Of these are simply
notes OF partial observations, and others are verbal
communications (as those Of Profs. Agassiz, Henry.
Bache, Rogers and some others which are con-
densed INTO succinct statements Some OF the larger
papers read only ~ their titles to be puohshea
In the Section of Mathematics and Physics, Prof.
LOOMS Chairman, and PrOf. GILLESPIE Secretary,
number of important papers were presented.
Prof J. LAURFHs SMITH announced the improve
ments in the Microscope achieved by MI Charles \.
Spencer, and exhibited the instruments.
Prof McCULLoH OF the College OF New-Jersey,
gave brief explanation oi the phenomena OF Ddi-
forism or blindness 10 particular coors.
MI JOHN PATERSON, Of Albany read communl-
cation on the Relation bCtWetn The Square Roots Of
Ngati,e QuaAttcs in Algebra, and the PraacPies of
Pfrp,nd.cuiarsfy IN Geometry. Mr.. Paterson Is
lourneyInan printer b. profession, and by ms own
efforts has attained high position as InathenHl'
cal scholar.
series Of communications on the Pendulum Ex-
periment of Foucault were successfully made by
Professors CAswELL and NORTON OF Brown unver-
sty Prof. JAs. u. DANA of wHayen, and Prof.
f. N. HoRsfoRD Of Harvard This matter being
one OF general interest, | annex the communica'
uons nearly IN tie oiGcr Of then delivery
THE PENDULUM EXPERIMENT OF FOU-
CAULT.
Stotcrnem of the Results of q set Of cbSrrat,ons
r,pftitton If Foucapifs EIpcrimentS; madc at
Prot1donce, II. l., by Profs. CasueH and Norton
The substance Of these observations was commu-
nIcateG by Prof. NORTON.
The denduium was suspended IN a tower al the
Railroad Depot building at Providence, and was 81
feet III length the weight was Little less than 10
lbs IL was a ball Of lead, nearly SPHERICAL through
the center OF which passed perfectly straight steel
rod, about of inch IN dldlnetcF. 1his rod
was tapered to point below the hall AT the other
extremity provided WIN q cap. 10 screw on
and off, for the more convenient attachment OF the
wire, which passed through small hole IN the cen
ter of the cap The leaden ball was cast around
the rod and then turned IN lathe.
BY careful trial II was found that the center OF
gravity was truly situated on the axis. The wlro by
which the weight was suspended, was Of brass, half
anneaed, and was .035 of an inch IN diameter. II
was attached AT the top TO screw bolt, passing
through a small hole in the head OF It.
All the openings In the tower were carefully closed
UP, to secure as tranquil state OF The AIR withnn
40 Hap Al lo xktS a flr
cuar table, little over FIVE feet in diameter the CIR
cumfeIencc OF which was divided into degrees. The
point OF the rod, when the weight was "A, rest, was
directly over the center of the table and within
small fraction of an inch OF H. The table was pro-
viuvd with index movoaulv around ltS center ana
extending entirely across 1t, and somewhat beyond
the outer circular rim At each end OF this index
was an upright sght.ydne, having slit traverSed by
fine thread, and also a yerniCr for reading the
giles. A black thread was stretched across from the
OF yernor 10 that of the other, and passing
through the center of the table.
In starting the pendulum, the weight was IrSt dl-
vested OF any tendency To roialory movement, and
then carefully and slowly dTaWno one side and at-
tachod 10 one Oi the upnghis by loop with single
cotton thread leading from II. The point OF the rod,
below the wels hit, Was then adjusted 10 the zero of
the contiguous vorncr, and aier II had become per
cctly still N this poSluon the thread was burnt. The
are of oscillation travCrScd the weight was about
81 feet, and the time OF oscillation seconds The
movement of the plane OF oscillation was followed
and meaSuredby moving the index. The obSerya-
tons were generally made every ten minutes. and
the angles read hy both OhSer,crS, each observer
having charge Of IA verner and usually were con
tnued for an hour. In one instance they were con-
tnuCd for three hours. Whenever the elliptic move
mcnt OF the weight, which was found almost ALWAYS
to arise after time To dgreaer or less extent, be-
came very marked the period OF observation Was
shortened TO half an hour, or even less. The OBJ
s,rvatlons made at all parts of The circle, that
~ the pendulum started from various points
that the plane of oscillation might, IL the outset,
have every variety OF position. IL VIII be perceived
that the observations were conductedn manner
calculated to eliminate errors OF graduation and &C.
centrclty. II ought To be stated however tha, the
numsor of observations hitherto made is not sufficient
10 warrant the conclusion that the mean OF the re-
suits of the individual obSer atoms Is very exact
peclaly as the graduation OF The circle was made by
hand. The number OF observations OF the movement
of the plane Of oscillation, during an interval of
hour or halihour, Is s3 In the case of four OF the
observations, the elliptic movement was so large that
the results cannot be relied upon and IN the of
three others the results differ widely from the
mean OF the others that they must be regarded
anomalous, and II Is accordingly believed that they
ought to be rejected The mean Is therefore derived
from only 10 observations. II can only be regarded
as an approximation TO the result sought. 1t pro-
posed 10 continue The observations, II practicable. IN
the hope OF obtaining closer approximation. AC-
cordng 10 the l6 observations taken into account the
mean motion per hour Is y s. 3 The theoretical
motion. IN The latitude OF Providence, Is To- OF 49,
that's greater than the result oithe obSe atoms
As 10 the amount of the elliptic movement observed
there was only one instance in which none was per
Ceptible during entire hour In the other ln>lan-
ceS the conlugae AVS was between zero and half an
inch IN length. In the case of the observations re-
Jected II amounted to an inch and hal, or more.
The soweSt motion observed was : 80 and the
most rapid TO- 81
|, does not appear tha, the irregularities observed
are attributable 10 the elliptic movement. Some OF
the largest dcylatCns nom the general mean oc-
CURED when this movement WAS slight. A. 10
the direction of the elliptic revolution Al Was. IN the
majority of instances indirect contrary thai OF
the motion hands OF a watch In onl, instances out
ofs3 was amo,on IN the contrary direction observed
oeserref'Ons Of Prof James D. Dana, Of Nf,r-Hare.
The peculiar interest of Snuraulf'S .x,ari,,an.
With the pendulum, by which the rotation az tbe
earth proved even within the walls oi am cnllnary
lecturc-TOom has obtained for very general afen-
iion, and II has already been repeated IN numerous
places IN tins and other countries The occnrrrnc,