: DEGREE, 
which are dane at large in the memoirs of the academy 
for 1751. About the fame period, Bofcovich, a sap Je- 
{uit, ond aad. pathemtca, meafured an arc of two 
degrees between Riminiand Rom ie are 43°, nu found 
the ee = 56,973 toifes. The x whole of this operation is 
aa 'y deferibe ise in a quarto book, oabiihe d at Rome in 
1755, De Litteraria Expeditione per Ponta Ditio- 
nem ne Dinetiendos duos ieee oe 
A tranfiation of this work appea in Te contains 
pata of feveral problems ae to the figure of 
theea 
MW flr rs. - Mafon and Dixon meafured a degree of the meri~ 
dian in America, a full account of which is to be fou 
the Phil. Trant. wie ay mode of meafurement aiffere 
from all others in this; that inftead of adopting the me 
thod of alee the ‘hole {pace was atually meatared. 
From this meafurem ent _ degree in latitude 39° 12’ a 
peared to be 56. st 
I 
Se hy i) 
Past 
7,024 t ile, 
ie in latitude 44° i Gradus 
» one in - ic gave 
a number, se 
‘In the month cember 1702, father Anthony 
Thomas, a iat. was ones by the emperor Kanghy S 
meafure a degree of latitude. For that urpofe, a very e 
tenfive plain was chofen, and the bufinefs a meafuring car- 
ied on in the prefenc e of all the mandarins of the mathe 
cal tribtinal, and even of o 
th, 1705, communicated to Major de Zach, at Gotha, 
as late as April 19, 1800, by Mr. Gabriel Keghe proleitor 
at re It is a pity that neither the de egree of lati- 
ethod of ea is pointed out in this 
From circumftan 
as 200 fhadia, it t may sed concluded that the — of menfu- 
ration they adopted was to meafure from end to the 
other of a ftraight line, extended to ae saekee of ftadia. 
If oe as it appear 8, has really been the cafe, it is aftonifhin ng 
how a method fo tirefome i in its nature, and fo imperfe@ in 
its pangs a oe a deus which a mee ire weak 
in queftion may claim a rank 2 exact opera- 
tions of this kind, performed a pe aan and on 
more aes princ 
When eonader how important it muft have been ] ie 
learned care at the court of oa that no great 
ou e committed in this operation, we fhou aoe ‘be 
fo much furprifed at the accuracy of ae refult, which moft 
eae was very little connected with the correéinefs of 
the procefs. 
We ee omitted to mention the aaa 
longitude, by Caffini and La Caille 
re of a degre € of 
of explofion of rolbs. of powder upon the church of 
t. Matic, a little village on the banks of the Rice. 
y a bafe fured near Arle es, they found the diftance 
1°55’ 19” = 41,358 toifes. 
lefs on the {pherical hypothe 
Notwithftanding thefe labours, great beer ied fill rs 
mained aay the true figure ofthe earth: the diffe cae 
meafures cou o means be made to agree with any pro- 
Suk hypothefis. The a seal refulting from thefe meas 
fures varied from 
Tt feemed diffcule 1 ao whether this sale arofe 
rom irregularity in the figure of th m errors in 
an meafurement. We now know that both hel caufes con 
to produce this difagreement. Later 
furveys have taught us oe plumb line is oad by 
i€s ; he asiclaluings of the true 
s an operation of 
much greater difficulty than was i that ca: imagined, 
It would have been 260 toifes 
fig. 
Q 
=} 
Account of the trigonometrical Operations carried on in England. 
n after the peace of 1783, a proje&t was undertaken for 
ameeae the obfervatories . Greenwich and Paris, phe 
gave rife to the c oo ruction of two inframen, fo gre 
excelling any t been ee wfly ufed i ee ee 
operations, that ee abfolutely for e {rience 
of trigonometrical furveying. One 
of Ramfden, the other the deetag circle o rda. (For 
a ao defcription of each, fee Tueoporirs and 
"The great i Sale gt en me of this kingdom origine 
ated in a great meafur orial of Mr. Caffini de 
Thu 
m conftrudting a feries of triangles 
ce t tfhould ¢ onne& trigonometrically the two obfervatories of 
Greenwich and Paris, and determining their relative 
pofitions, more accurately than it was cas could be done 
by aftronomical aly ation. 
sige were 
been much engage 
{maller ca. chiefly with a 
7 rft confideration was to find an appropriate place 
for the meafurement of a bafe; and ead -heath was fe- 
lected for that Ar ae both from its great extent, and the 
— aro 
ce of ae five En miles It oO 
ha dann that this line os with a remarkable {pire 
feen at the diftance of 10 0 miles, known afterwards to 
belong to Banftead church, “'T his object was of confiderable 
ule 
