Hijlory of AJlronomy for 1798. 23 



ta'med gold by treating filver with common fait. M. Cappel, 

 by treating filver with arfenic, obtained from four ounces ten 

 grains of gold *. Guy ton confirms this experiment, and 

 obferves that, in this manner, 8 grains of gold are obtained 

 from 1000 grains of filver f. The arfenic, in the laft cafes, 

 was combined with gold. Some very important refults, in 

 regard to this fubjeft, might be obtained by examining the 

 works of the ancient alchemifl:s, as all their aflertions re- 

 fpe6ling real tranfmutation might be explained by mere fe- 

 paration, without allowing them fo much as fome have 

 done X, 



V. Hifiory of AJlronomy for the Year 1798. Read in the 

 College de France, Nov. 20. ^ Jerome La land e, 

 Infpetior and Dean of the College, and formerly Diretlor of 

 the Ohfervatory. 



I 



[ConcluJed from the laft Volume, page 3S9.] 



SAW at Strafburgh the firfl; fheets of a new map of 

 Swiflerland conftrufted by M. Weifs, to whom M. Tralles 

 com.municated his triangles and bafes. This map is ex- 

 tremely well engraved, and gives us an interelling topogra- 

 phy of Helvetia. 



I paid a vifit, in my paffage, to the ubfervatory of Man- 

 heim, which had afforded me fo much pleafure in 1791 ; 

 but I found the inftruments packed up in boxes and de- 

 pofited in vaults which the bombs had fcarcely refpefted, 

 and waiting there for peace, without which neither fcience 

 nor happinefs can exift. The miniftcr d'Arberg, whom I 

 requeficd to fccond the zeal of M. Barry, fhewed me every 

 mark of friendship. 



• Crell's lle.ufflc entdeckunveti, vol. x. p. 136. 



+ Crell, utfupra. 



X See CrcH's Ncues Lhetn. Archi-v, vol. i, p. iii. 



C4 On 



