DEG 
wholly on an error in the amplitude of the are which he ef- 
timates at 10” or 12” 
Thefe are the fides common to both the operations. 
Swanberg. Outhier. 
- 7414-5 740 
Bafe - - - : - re 6 
Northern extremity to Avanfaxa 1186. 1207.3 
Southern extremity - Avanfaxa G240.0 7242.3. 
Cuitaperi - Avanfaxa 86569 8660.0 
vitaperi - Horrilankero  13396.1 13432.0 
Keakamavara - Horrilankero 19066.5 19073.0 
Kakamavara - Niemifby 25047.0 25053.0 
Horrilankero - Niemifby 7028.4 7029.0 
Horrilankero - Avanfaxa 447.90 74504 
Pullin - anfa 4271.0 14277.3 
Pallingt - Horrilankero 11529.3 11558.5 
Pallingi - Niemifb 757.6 8768.8 
Pullingi - Kittis 10672.3. 10676 
Niemifby - Kittis 13449.1 13560.0 
The obfervations which were made to determine the lati- 
tude of the extreme ftations gave likewife, with the greateft 
accuracy, the declination or polar diftance of the pole- ftar. 
Mr. Swanberg deduces it from his obfervations 1° 45’ 36”.2, 
for the beginning of year 18003 Delambre and Mechain, 
from the mean of fome hundred obfervations, 1° 45’ 35”.43 
by Mr. Pond’s tables in Philofophical TranfaGions inferted 
under DecLinaTion, it is 1° 45’ 36" eh aH pofition 
of no ftar was ever fo well known. The a Mr. 
‘Swanberg’s meafurement and calculation is as . ile 
The length of the bafe reduced to-the level of ie fea, at 
was 7414.4919 toifes, o 
245i. , ance between the parallels of 
ves and Mallorn es 981 toifes or 180,827.68 
The latitude of the centre of the fignal y Mallorn was 
65° 31/ 30".26, and at Pahtavara 67° 8! 4 _ efore 
the latitude of the middle point was 66° 20! ie 04 § : m- 
plitude of the whole arc 1° 39'19".563 and the le fh the 
—. 57,196.159 toifes. The moft ees ellipticity 
duced from comparing thefe determinations = thofe 
made in Peru, the Eaft Indies and a is » and 
the radius of the equator 3371452 
Maupertuis exceeds that 
ee 
of Mr. Swanberg 9 
eru 
equal error in their fe anion the pclae axis mou have 
appeared the longe 
The account which Mr. Te has publifhed of this 
dale is enriched with a of valuable invefliga- 
various formule, for ie eneuatan and correction 
of ipheroidia triangles and of the different parts of. a me-- 
ridian lin entitled ‘* Expofition des Operations faites 
rg pee ee i: Det: rmination d’un Arc du Meridien, 
en 1801, 1802, & 1803, par Meflieurs Ofverbom, Swan- 
berg, Holmquitt, et Palander. Redigée par M. Swan- 
ber 
The mathematical clafs of the national inftitute, as a 
mark of refpeé&t to M. Swanberg, for the {kill and analytt- 
cal knowledge difplayed in the above work, voted him the 
medal founded De la Lande. wv. Con. des Temps 
1808, from which this account was chiefly taken. 
Meafurement of a meridional and perpendicular Arc ia India. 
Ia the Afiatic refearches, (vol. viii. } major Lambton has 
given a very circumitantial account of the meafurement of 
REF, 
an arc of the a on the coaft of Coromandel, in the la~ 
tude 12° operation form 
fae: ae is sinenties to be lei seal the peninfula of 
ndia. It appears to ks been con i intelli 
St. 
: eorge, and extended 40006.44 feet, in a direGion nearly 
ou 
The angles were meafured bya theodolite extremely fimi- 
lar to ci ufed in the 
ary, an arti whee was brought up under Ramfden, 
and nothing inferior to him in the beauty and delicacy of his 
workman 
The canals which connected the extreme fl:tions were 
eat never pro- 
bably et 2", and was often within that quantity. The 
fouthern extremity of the arc was at Trivandiporum, in lat. 
1k 52". 6, near Pondicherry ; the northern at Paudree, 
lat. 13° 19’ 49”. 
he ena ae to determine the amplitude of the 
arc were made with a zenith feétor, conftruéted by Ramf 
whole of this operation 
in a manner that refle€ts great honour on himfelf and his pro- 
€ : 
° 
ao 
ct 
2& 
‘Ss 
ct 
im 
oO 
rs) 
8 
jm 
ce 
bp 
we 
~~ 
2 
R, 
a 
a 
Ss 
“ 
Q 
° 
3 
ns) 
= 
5 
On, 
ad 
oon 
om 
a 
= 
i=) 
fd 
udicious 3 it wou e been more ftriGly corre& to have 
taken, for afeconda aie a ne {pheroid derived from 
his own obfervations ; but as he hi 
mbton obtains 18, that the 
c61 Fat thoms. 
We have now Te ekt the birial part of our fubjeé& 
a conclufion, and have enumerated e ope ene eae 
for the meafurement of the earth hers is found upon record; 
from the earlicft ages to the prefent da 
It is evident that the late attempts to inveftigate the exa& 
confider the exquifite conitruQion of the inftruments that 
have been contrived for this purpofe, the intelligence that 
has. 
