g58 French Natioiial hijlitute. 



INTELLIGENCE, 



AND 



MISCELLANEOUS ARTICLES. 



LEARNED SOCIETIES. 



FRENCH NATIONAL INSTITUTE. 



'N the 4th of July laft, the following account of the la- 

 bours of the Mathematical and Phyfical Clals during the 

 preceding three months, was read by C. Cuvier, fecretary: 



The antients admitted only four elements, by the com- 

 bination of which they fuppofed all other tcrreftrial fubftances 

 to be formed. Modern chemiftry has rejefted this vulgar 

 opinion, and has given the name of elonentarj to all fub- 

 llances which it is not able to decompofe, but it at the fame 

 time endeavours to diminifli the number of them ; and when- 

 ever it is able to prove that a fubflance, which appears to be 

 fimple, refults from the combination of two others, it obtains 

 the double advantage of fimplifying the theory of the fcience, 

 and of being able to reproduce, at pleafure, that fubftance, 

 with the analyfis of which it is acquainted. 



It appears at prefent that it is on the eve of a difcovery of 

 this kind in regard to two fubftances, very inlerefting on ac- 

 count of the part which they aft throughout nature, and of 

 the ufe towhich thev are applied in the arts. I here allude 

 to the acid of fea-falt, called by the modern chemifls the 

 muriatic acid; and the two fixed alkalies,y&r/i2 and potc/Jh, 



It has lately been difcovered, that almoft all the acids are 

 obtained from the combuftion of certain fubftances ; the fub- 

 ftance which muft be burned to obtain an acid is called the 

 radical of that acid, that is to fay, according to the pneu- 

 matic theory, which niuft be combined with oxygen to pro- 

 duce that acid. The f/iarine acid was one of thofe the ra- 

 dical 



