23 
April, 1824, in the 20th number of the Edinburgh, llemcw 
(page 280), in which I expressed an opinion that the cohesion 
of the bodies constituted on the surface of the earth may be 
liable to attraction, which will tend to join in their centre of 
gravity the composed molecules. I also explained the great 
difficulty I had in attaining this result. Indeed, if the par- 
ticles of invisible and invaluable bodies could maintain their 
distances by the same laws as the celestial bodies, the former 
Avould necessarily be perceived, for they would be obliged to 
collect themselves in a symmetrical and regular manner about 
their centres of gravity, and make their movements apparent 
to our senses. I have understood since that a law exists, 
unknown to me, determinating the organised parts of bodies 
to keep a distance and to preserve the permanent forms they 
exhibit. Therefore I studied incessantly to solve a question 
of so great an interest, and in 1836, after twelve years passed 
in study and meditation, I was fortunate enough to succeed. 
Indeed, an attentive examination of the manner of action 
exercised reciprocally by the particles and generally by all 
the bodies brought this result : If systems of two or several 
molecules, being comparatively in repose, traverse other 
systems comparatively in movement, the former separate the 
latter from another, losing a part of their own movement. 
Consequently, the question of cohesion was for me implicitly 
resolved ; and, after eleven years’ further reflection, I began 
to publish (in 1848) the series of papers I have read in the 
Institute, and in which I proved, under the name of Dis- 
tension, the new result of Newton’s attraction applied by 
myself. 
“ Then, making myself better acquainted with this law, I 
published, in 1855, a large volume upon cohesion, and in 
1859 another upon the origin and propagation of force, in 
which I have perfectly explained these principles, trusting to 
my own proofs and experience. Moreover, I published in 
1861, in the form of a letter addressed to M. Tramblay, 
director of the Cosmos, a third paper in reference to the same 
