328 Biographical Account of [May, 



This memoir, printed like the preceding, among those of the 

 Turin Academy, is notwithstanding dated Berlin, the 20th Sep- 

 tember, 1 768. This date points out to us one of the few events 

 uhich render the life of Lagrange not entirely a detail of his 

 ■writings. 



His stay at Turin was not agreeable to him. He saw no person 

 there who cuUivated the mathematics with success. He was im- 

 patient to see the philosophers of Paris, with whom he corresponded. 

 M. de Caraccioli, with whom he lived in the greatest intimacy, 

 was^ appointed ambassador to London, and was to pass through 

 Paris on his way, where he intended to spend some time. He 

 proposed this journey to M. Lagrange, who consented to it with 

 joy, and who was received as he had a right to expect by D'Alem- 

 bcrt, Clairaut, Condorcet, Fontaine, Nollet, Marie, and the other 

 philosophers. Falling dangerously ill after a dinner in the Italian 

 style given him by Nollet, he was not able to accompany his friend 

 to London, who had received sudden orders to repair to his post, 

 and who was obliged to leave him in a furnished lodging under the 

 care of a confident charged to provide every tiling. 



This incident changed his projects. He thought only of return- 

 ing to Turin. He devoted himself to the mathematics with new 

 ardour, when he understood that the Academy of Berlin was 

 threatened with the loss of Euler, who thought of returning to 

 Petersburgh. D'Alembert speaks of this project of Euler, in a 

 letter to Vohairc, dated the ,'5d March, 176G: "I shall be sorry 

 for it," says he, " he is a man by no means amusing, but a very 

 great mathematician." It was of little consequence to D'Alem- 

 bert, whether this man bi/ no means amusing, went 7 degrees 

 nearer the pole. He could read the works of the great mathema- 

 tician as well in the Petersburgh Memoirs as in those of Berlin. 

 What troubled D'Alembert was the fear of seeing himself called 

 •upon to fill his place, and the difficulty of giving an answer to 

 offers which he was determined not to accept. Frederick in fact 

 offered him again the place of President of his Academy, which he 

 liad kept in reserve for him ever since the death of Maupertuis. 

 D'Alembert suggested the idea of putting Lagrange in the place of 

 Elder, liiiA, if we believe the author of the Secret History of the 

 Court of Berlin, (vol. ii. p. 414,) Euler had already pointed out 

 L.t,:;raiige as the only man capable of fiiling his place. In fact it 

 was natural that Euler, who wished to obtain permission to leave 

 Beilin, and D'Alembert who wanted a pretext not to go there, 

 should both of them without any communication have cast their 

 eyes on the man who was best fitted to maintain the eclat which 

 the labours of Euler had thrown round the Berlin Academy. 



Lagrai.ge was pitched upon. He received a pension of 1500 

 Prussian crowns, about 250/., with the title of Director of the 

 Academy for the Physico-mathematical Sciences. We may be 

 surprised that Euler and Lagrange, put successively in the place of 

 Maupertuis, received only the half of his salary, which the king 



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