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superintend, under the direction of the late Mr. Rennie, the exe- 

 cution of that great national work, the Breakwater at Plymouth. 

 He was the author of three papers in our Transactions : one on the 

 means adopted for raising the Dutch frigate Ambuscade, which had 

 been sunk at the Nore ; and the other two on certain fossil bones 

 discovered in the limestone quarries at Oreston, near Plymouth. 



Adrien Marie LeGendre, one of our Foreign Members, and one 

 of the most illustrious analysts in Europe, was born in Paris in 1752, 

 and died on the 10th of January last, in the eighty-first year of his 

 age. After the completion of his studies at the College Mazarin, he 

 devoted himself to mathematical and scientific pursuits, which he 

 continued, with singular perseverance and industry, for the remainder 

 of his life. At the age of thirty he gained the two prizes proposed 

 by the Academies of Berlin and Paris ; the one for a memoir on the 

 motion of projectiles in a resisting medium, and the other for a me- 

 moir on the attraction of spheroids upon any external point what- 

 ever. It was this second memoir which gained him, in the follow- 

 ing year, a place in the Academy, as the successor of D'Alembert, 

 and which attracted in a peculiar degree the attention of mathema- 

 ticians. The problem which it treated was one of the greatest im- 

 portance and difficulty, particular cases only of which had been suc- 

 cessfully treated by Newton, MacLaurin and Clairaut, but which he 

 attacked in all its generality, and mastered its difficulties " sword 

 in hand," to use the expressive language of Lagrange, when speak- 

 ing of this admirable memoir. An important proposition discovered 

 by Laplace led to a second, and a happy substitution, proposed and 

 applied by Mr. Ivory, to a third resumption of this problem, which 

 has finally terminated in such an organized system of approaching 

 its difficulties, that it has lately been reduced to the order of those 

 propositions which are included in the higher class of elementary 

 books *. 



It was in the course of his researches upon the attraction of 

 spheroids that his attention was first drawn to the subject of elliptic 

 integrals, concerning which his first memoir was published in 1786. 

 He continued to pursue this most interesting and difficult branch of 

 analysis in a succession of works, for a period of nearly forty years, 

 and had finally collected his entire labours upon it in two volumes 

 quarto, which he published in 1827, forming a vast treasure of ana- 

 lytical knowledge. He had hitherto laboured in this field without a 

 colleague and without a rival, when two young analysts of singular 

 genius and boldness, M. Abel, of Christiania in Norway, and M. Ja- 

 cobi, of Konigsberg, announced, almost simultaneously, the discovery 

 of propositions which have led to an immense extension of this the- 

 ory. LeGendre, with a nobleness of character which can only result 

 from the most disinterested love of truth, was the first to welcome 

 the appearance of these illustrious strangers upon his own territories, 

 to make known the full importance of their discoveries, and to de- 

 velope all their consequences ; and although already arrived at an 



* Poisson, (Traite de Mecanique, second edition,) who has obtained an expres- 

 sion for the attraction under a finite form. 



