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> 
so “Se SOR Seeatgs 
[Nov. 1, 
PROCEEDINGS OF LEARNED SOCIETIES. 
NATIONAL INSTITUTE. 
Report. on the _ Progress of the Sciences 
rem the Epock of the French’ Revoles 
dtom (4789) te the Fear 1808, made by 
@ Commission of the Instivute of Frence, 
by order of the Emperor Napeivon. 
( Continned from our fast.) 
HE honorable duty which the or- 
ders of your Imperial Mosjesty call 
wpon es to fulfil, rtimidates us equally, 
whether we consider the extent of the 
eciences, the history of which we have te 
trace, or the number and the arder of 
those who cultivate them, er the rapidity 
ef the progress which they have made, 
during the last twenty years; and it is 
not without awe, that we hare ventured 
to select, among such a variety of la- 
hours, and among So many men of dis- 
tinguished merit, those who have ap- 
peared to us most worthy of being named* 
to you. Indeed, could the dread of 
having been guilty of an unjust omission, 
ever be more sensibly felt, than on this 
solemn occasion; when genius requires 
to become acquainted with, and to he- 
nour genius, when the here, who has ex- 
tended military and political glory be 
yond the limits assigned to it by all the 
examples of history and the boldest 
fights of imagination, wishes to draw 
near him, and to crown with his own 
hands, every species of merit, to encou- 
rage every kind of talent, and to order 
the execution of every usetul under 
taking. 
Bat in what branch of human know- 
ledge is such an omission mere dificale 
to be avoided, than in the natural sce 
ences, a held atthe same time the most 
boundless, and the most fruitfalthat the 
mind is capable of cultivating? Their 
most general principles are not vet re- 
duced to precise calculations, and con- 
sequently they admit of no other guides, 
than observation,and experience ; but by 
A conseguence vot less evident, every 
accurate observation, every conclusive 
‘experiment, is entitled to a place amongst 
these sciences; and the particular ja- 
ours employed on them, which their: 
historian is ret at hberty to neglect, are - 
multiplied beyond all bounds. 
Ths prodigious number of facts, ex- 
tending from the simple aggregation ef 
the molecules of a salt, to the fermation 
ef organised bodies, and to the most 
complicated functions of fe, seems, how. 
ae “Le 
ever, to relate more or less immediately 
to the general phenomenon of molecular 
attraction ; and we could net have chosen 
a more convenient clue, to direct us 
through this immense labyrinth, 
We have, therefore, first examined 
molecular attraction, in its most immedi- 
ate effects; in the laws to which it is 
subject, and in the modifications which 
it undergoes, from the other general 
principles ; to this we ewe the advantage 
of beginning our repert, with the theory 
of crystals, and that of the aflinities, two 
sciences enurely uew, and originating 
within the period of which we have to 
treat, 
The former, which distinguished its 
commencement, is entirely due to M. 
Haiiy; those figures-so regular, and so 
varied, which minerals assume in a tran. 
quil formation, are now reduced to cal. 
culation, and verified by mechanical di. 
vision; this curious phenomenen offers 
nothing arbitrary, nothing vague in its 
explanation; the same age, the same 
author, have seen thé birth of the sci. 
ence, and have, as it were, brought it te 
maturity. ; | 
_ The theory of affinities, more ancient 
as to its primitive origia, has recently ex- 
perienced a complete revolution; and 
M. Berthollet has reduced it to new 
laws. He no longer admits of elective 
affinities, nor absolute decompositions ; 
athnity, with him, 38 no more than a ges 
neral tendency of a body, to unite itself 
with others, which would conti..ve to 
operate when three or more bodies are 
mixed, were it not counterbalanced by 
é 
opposite forces, such as the indissolas 
bihty of one of the resulting combina- 
tions, or its greater tendency to crysta- 
lize, to efloresce, or to evaporate. In 
short, heat and pressure are powers Op- 
posite to'each other, which cause affinity 
itself to vary in different wayse as well as 
the tendencies which are contrary to 
it. We shew particularly in our. 
that these principles throw a vivid light 
on what was hitherto most obscure in 
chemistry; and we render perceptible 
the influence which they will one day 
exercise on all the other physical scm 
ences. . 
Proceeding next to the divers impone 
derable agents, which cause the affinities 
to vary, we say a few werds on the che- 
mical action of light, aad on the hitherto 
a . : contested 
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