‘292 French Royal Academy of Sciences. 
Secretaries :—John T. Conquest, M.D. F.L.S.; Thomas 
J, Armiger, esq. 
Council : 
Thomas. Addison, M.D. James Alexander Gordon, M.D. 
Thomas Bell, esq. F.L.S. William Kingdon, esq. 
Henry James Cholmley, M.D. | Benjamin Pierce, M.D. 
Thomas Calloway, esq. James Parkinson, esq. 
William Cooke, esq. Henry Richard Salmon, esq. 
George Edwards, esq. Frederick Tyrrell, esq. 
ROYAL ACADEMY OF SCIENCES, PARIS.* 
In the public sittings of 22d March, was read.a Notice on the 
continuation of the labours:undertaken to determine the figure 
of the Earth, and upon the results of the operations of the Pen- 
dulum, made in 1817, at the Shetland Islands, by M. Biot. 
The paper commenced ‘by a reference to a notice read ‘last 
year before the Institute, detailing the birth and progress of the 
great system of astronomical observations, undertaken a century 
and a half ago by the Academy of Sciences, and followed up, with- 
out interruption, since ‘that epoch, in all. parts of the world, to 
determine the figure of the earth, and, what isiperhaps more 
surprising, to. discover that law of density, according to which, 
matter is distributed.in the beds which form the interior of the 
mass_of the earth. 
The author then proceeded to remark that, “ if a century ‘and 
avhalf of experiments were necessary to develop and to perfect 
all. the means which the solution of this great physical question 
required, now that those means. have been acquired, our progress 
will be more rapid. The short space of a year has been sufficient 
to add tothe results already obtained new elements, which both 
confirm and enlarge them. These recent acquisitions we now 
propose to submit to you. 
“* The figure.of the earth may be determined by two methods, 
the results\of which will be found to agree, though the processes 
are different. In.the- first, whichis purely geometrical, the ob- 
server measures .in‘reality the length.of an-are of the terrestrial 
meridian,—that is to say; let him measure, - provided he can: do 
it immediately on the earth, the whole of that are, in a'straight 
line, as was done in Pennsylvania 50 years ago ; but if the con- 
figuration of the:ground,and if the ‘habitations which cover it, 
do not permit him ‘to extend his operations, as is commonly ‘the 
case, he measures, ‘first of all, aline of four or five thousand 
toises, with ‘the utmost precaution ahd accuracy: then, upon 
* From the Moniteur of April 5. 
this 
