242 Biographical Sketch of M, Proust, [Oct, 



From the lectures and conversations of Rouelle, he imbibed 

 his decided taste for this science, and also, perhaps, that 

 original and acute mode of thinkiho; which was so eminently- 

 characteristic of his master. Rouelle was a competent judge 

 of talent ; he assisted the young chemist with his advice, 

 honoured him with his friendship, and facilitated the commence- 

 ment of that career which he continued with so much success. 



During the time that he retained his situation at the Salpe- 

 triere, Proust wrote and published several notices and memoirs, 

 among which may be mentioned his Researches on Urine, his 

 Essay on Phosphoric Acid, a Memoir on Pyropliori without 

 Alum, Experiments on the rapid Combustion of Essential Oils 

 by Nitric Acid, Sec. He discussed the opinions which had been 

 previously broached on the subjects of which he treated, and he 

 early evinced that indepenidence of mind which afterwards 

 appeared in his scientific researches. w-iVuV. '.•>•> 



Proust was known at this period not only oy rfie works which 

 he published, but also by teaching chemistry with great success 

 in the Musee du Palais Royal, and also in a private establish- 

 ment founded by the unfortunate Pilatre de Rosier. He accom- 

 panied this philosopher in his first aerostatic ascent, which took 

 place at Versailles on the 23d of June, 1784, in the presence 

 of the Court, and of the King of Sweden, who witnessed this 

 exhibition for the first time. The balloon rose at first with 

 some difficulty, and the rapid oscillations caused by the wind 

 occasioned a momentary apprehension for the safety of the two 

 aeronauts; but being soon freed from the shackles which 

 detained it on earth, it rose majestically into the lofty regions 

 of the atmosphere, and speedily allayed the fears of the multitude 

 for the safety of the intrepid navigators. 



This aerial voyage, the longest which had till then been made, 

 and the account of which is extremely curious, was crowned 

 with complete success ; the balloon descended without any 

 damage, in an hour and seven minutes, at thirteen leagues from 

 the place of ascent. Proust peremptorily refused to have any 

 thing to do with the second ascent, the danger of which he 

 foresaw.'* It was not his fault that the unfortunate Pilatre did 

 not escape the deplorable accident of which he was the victim, 

 and which too well justified the melancholy forebodings of the 

 chemist. 



The Spanish government, observing the progress which the 

 physical sciences were then making in France, and foreseeing 

 the resources which they might afford to the industry of a 

 people, offered Proust a professorship in the School of Artillery 



♦ This second ascent was made by combining the process of Montgolfier with that of 

 Charles ; there were two balloons, the upper one was fiUed with hydrogen gas, and the 

 lower one with air expanded by heat ; that which Proust had foreseen occurred, the 

 hydrogen gas took fire, and Pilatre de Rosier was precipitated from the air, with a com- 

 panion, who, wishing to participate in his glory, shared Jiis fate. 



