Latitudes of Montjouy and Barcelona. 265 



latter years. From the moment that his mind dwelt on these 

 supposed errors, from the day when he adopted the fatal reso- 

 lution of concealing the principal one, in the hope of returning 

 to verify his observations, the happiness which he had hitherto 

 enjoyed entirely forsook him. The weight of his secret, the 

 accident which endangered his life, his wearisome captivity, the 

 fatigues which he endured with so much perseverance, the 

 separation from his family at that unsettled period, without 

 obtaining tidings of them for many months, all combined to 

 change his character, and to produce a state of melancholy, 

 reserve, irresolution, and sometimes of apparent indifference 

 and inactivity, which his friends in vain sought to comprehend 

 or to overcome. Ten years were passed in crosses and disap- 

 pointments which embittered and shortened his life. Mechain 

 died at a distance from his country, his family, and his friends, a 

 victim to the zeal and devotion with which he pursuedthe objects 

 of his employment; and deprived of that period of life when 

 he might have enjoyed the consideration and celebrity to which 

 his services so justly entitled him. His name, inseparable from 

 that of Delambre, remains, however, honourably attached to 

 operations which will preserve the high station assigned to 

 them amidst the achievements which distinguish the progress 

 of science in the eighteenth century. 



J. N. Nicollet. 



On the Annealing of the Specula of Reflecting Telescopes* — 

 By J. Mac Culloch, M.D., F.R.S., &c. &c. 



(Communicated by the Author.) 



It is much more than twenty years since I spent some time in 

 constructing specula for reflecting telescopes; nor, till very 

 recently, had I any reason to conjecture that in any part of 

 the process, which it was my lot, like that of others, to labour 

 through for myself, I was possessed of knowledge which was 

 not equally known to every one who had attended to this sub- 

 ject — much more to the makers of such telescopes. Having 

 lately, however, had an opportunity of conversing with Mr. 

 Ramage about his processes, I believe that there is one point 

 at least which has been misunderstood, and, consequently, 



S2 



