ALEMBERT. 



thrinatics; hut they soon perceived that 

 < fmient to this science 

 v. aslikelv to disappoint tke hopes they 

 badfonned witli respect to his future des- 

 ired to 



divi-rt liim from tlie pursuit; hut thc-ir 

 emit avours were fruitless. 



On his quitting' the college, find ; ng 

 himself alone, and unconnected in the 

 world, he sought an asylum in the house 

 of his nurse, who was the wife of a gla- 

 zier. He hoped that his fortune, though 

 not ample, would enlarge the sub* - 

 and better the condition of her family, 

 v.'hich was the only one that he could 

 consider as his own. It was here, there- 

 fore, that he fixed his residence, resolving 

 to apply himself entirely to the study of 

 geometry. And here he lived, during the 

 space of" 30 years, with the greatest sim- 

 plicity, discovering the augmentation of 

 his means only by increasing displays ( >f 

 his beneficence, concealing his growing 1 

 reputation and celebrity from these ho- 

 nest people, and making their plain and 

 uncouth manners the subject of good- 

 . ;itur.(l pleasantry and philosophical ob- 

 -'ii. His good nurse perceived his 

 ardent activity ; heard him mentioned :'.s 

 the writer of many books; and beheld 

 him with a kind of compassion : "Von 

 will never," said she to him one day, 

 "be any tiling but a philosopher and 

 what is a philosopher ' a fool, who toils 

 and plagues himself all his life, that peo- 

 ple may talk of him when he is dead." 



mbert's fortune did not far 

 d the demands of necessity, his 

 friends advised him to think of some pro- 

 fession that might enable him 10 increase 

 it. He accordingly turned his views to 

 he luw, and took his degrees in that fa- 

 eulty, which lie soon at'ur abandoned, 

 and applied himself in the study of me- 

 dicine. Geomet" always 

 drawing him !>CK 

 so tha- 



to resist its at t net ions, he renounced all 

 views of a lucrative [> 

 himself up entirely to math 

 poverty. In the year 1741 he was ad- 

 mined a member of the Academy of Sci- 

 ences ; for which distinguished literary 

 promotion, at so early an age (24,) he 

 had prepared the way, by correcting the 

 errors of t!, 



Heyneau, which was highly esteemed in 

 Trance in the line of analyt 

 wards set himself to examine, wi 

 tiou and assiduity, what miiht be the mo- 

 tion and path of a body, which passes 

 from one fluid into another densr fluid, 

 VOl. J 



in a direction obl'que to the surface be- 

 tween the two fl - after 

 ion to a place in the academy, he 

 published h on Dynrr 

 The new prinr.Snle d 



lit\ . a' 



:-gone, 



and the forces or powers which h:n 

 employed to produce them; or, to ex- 

 press the same thing otherv ' 

 rating into two parts the action of the 

 ,d c'Hisid'-'-iii;; the one 

 as producing alone the motion of the bo- 

 dy in the second instant, and the other 

 as employed to destroy that which it hud 

 in the first. 



So early as the ; n'Alembeft 



had applied this principle to K 

 the equilibrium, and the motion of fluids ; 

 and all the problems before resolved in 

 physics became in corol- 



laries. The discovery of this new prin- 

 ciple was followed by that of a new calcu- 

 lus, the first essays of which were pub- 

 lished in a " Discourse on the General 

 of the Wind 1 '':" to this the prize- 

 medal was adjudged by the Academy of 

 Berlin, in tli "-, which proved a 



new and bi-illi;m; addition to the fain.- of 

 D'Alembert. This new calculus of "Par- 

 tial Differences" he applied, the year fol- 

 lowing, to the problem of vibrating; 

 chords, the resolution of which, as well 

 as the theory of the oscillations of the air, 

 and the propagation of sound, had been 

 butims ven by the mathemati- 



cians who preceded him ; and these w ere 

 his masters or his rivals. In the year 

 1749 he furnished a method of apply, 

 ing his principle to the motion of any 

 body of a given figure. He also re- 

 solved the probk>m of the precession of 

 the equinoxes: determining its quantity, 

 and explaining the phenomenon of the 

 nutation of the terrestrial axis discovered 

 by Dr. Bra. 



In 1752, D'Alembert published a trea- 



the " Resistance of Flu 

 which he gave the modest title of an 

 ** Essay," though it contains a multitude 

 Jial idea.-, and new observations. 

 About the same time he published, in the 

 M -moire of the Academy of Merlin. "He- 

 sea^ches concerning the Integral Calcu- 

 lus," which is greatly indebted to him for 

 the rapid progress it has made in the pre- 

 sent century 



While the studies of D'Alembert were 



confined to mere mathematics, he was little 



known orcelebrated in his native country. 



His connections were limited to a s 



N 



