16 Memoir of M. D' Auhuisson de Voisins. 



of the hour, the warmest hour giving the heights sensibly 

 greater (about a thousandth as a mean of total elevation.) 

 This influence he ascribed principally to the excess of rever- 

 beration to which the solar radiation was subject in a low 

 station, which changed the law of temperature in the strata 

 of air. 



All the results above alluded to, were stated in a beauti- 

 ful memoir read to the Institute in March and April 1810, 

 which received the most flattering approbation. 



But these valuable scientific researches did not make 

 M. D'Aubuisson forget the duties demanded of him by his 

 ofl&ce as an engineer ; on the contrary, he fulfilled them with 

 an activity and success, to which the peculiar state of this 

 country gave additional value. During his residences in 

 Paris, the administration likewise called in the aid of his 

 knowledge in preparing the law on mines, and on the func- 

 tions of the body of civil-engineers ; he thus obtained a claim 

 to advancement, which, besides, he might have been allowed 

 legitimately to expect on the ground of age. In 1811, on the 

 new minera^ogical subdivison of the territory, he was no- 

 minated engineer-in-chief of the arrondissement of Toulouse, 

 then very extensive. 



M. D'Aubuisson's wishes were thus fulfilled. Restored to 

 his native country, in a position if not brilliant, on the score 

 of fortune, at least highly respectable, and calculated to in- 

 dicate his personal merit ; and to this modest position, he 

 afterwards confined all his ambition, only seeking to adorn 

 and exalt it by his labours. Many others, in his place, might 

 have thought that as the future was henceforth secure, the 

 hour of repose was now come ; but such a mind as that of 

 M. D'Aubuisson knew nothing of cessation or rest. Instead 

 of looking for a termination to his labours in his new posi- 

 tion, he only saw an opportunity of enlarging their sphere, 

 and of being useful, at once to science, to the state, and to 

 his native city. To the latter, as we shall soon have occa- 

 sion to mention, he rendered eminent services during a re- 

 sidence of thirty years, but particulai'ly dui'ing the fourteen 

 years in which he acted as municipal counsellor. 



(To he concluded in our nenct number.) 



