made in the Coquille by M. Duperrey. 209 
Trials, opposite De Witt’s land, by 20° of south latitude and 
100° west longitude; M. Duperrey, who would have attached 
a great value to the determination of ‘their position, was not 
able to find them. 
The archipelago of the Carolines was repeatedly sailed 
through and minutely examined. M. Duperrey shows satisfac- 
torily that Hope island, Teyoa island, the groups of Satahual 
and Lamurek, do not exist in the positions which are assigned 
to them. Perhaps it may be sometimes difficult for him exactly 
to apply these old names to the islands whose place he has 
fixed. Moreover, the inconvenience is not serious; all was so 
inexact in the charts of this archipelago, that the labours of 
the Coquille are equivalent to a first discovery. 
Astronomical Observations. 
In a voyage like that of the’Coquille, in which the periods 
of lying-to were always necessarily very short, the astrono- 
mical observations could only have for their object the im- 
provement of geography. These observations, in each port, 
consist of elevations of the sun and stars fit for verifying the 
rate of chronometers; of numerous series of circummeridian 
heights taken with the astronomical repeating circle, and de- 
signed for giving the latitudes. Lastly, of a multitude of 
distances from the moon to the sun, to the stars and to the 
planets, taken with the reflecting repeating circle. 
The examination which we have made of the part of this 
labour already completely reduced, has given us a most fa- 
vourable opinion of it. All the officers of the Coquille have 
equally assisted in it. We must here, however, make particular 
mention of M. Jacquinot, who, intrusted by the commander 
with the care of the chronometers during the whole voyage, 
fulfilled this critical task with a zeal and exactitude worthy of 
the praises of the Academy. 
Observations relative to the Determination of the Figure of the 
Earth. 
M. Duperrey was furnished with two invariable pendulums 
of copper, which had before served in the voyage of the Uranie. 
They had been observed at Paris before the departure, and 
after the return of the expedition; at Toulon, whilst the vessel 
was fitting out; at the Malouines, 51° 31’ 43” south latitude ; 
at Port Jackson, on the eastern coast of New Holland; at the 
Isles of France and Ascension, between the tropics. Our col- 
league, M. Mathieu, has already calculated the observations 
for the Malouines and those of Paris. He has deduced from 
them this important consequence, at variance with an opinion 
long accredited, that the two terrestrial hemispheres north 
Vol. 67. No. 335. March 1826. 2D and 
