49 
OBSERVATIONS. 
* 
8 grains of which were diffolved in aqua 
regia, and added to the firfh folution. The 
infoluble 5 grains were feparated by the 
filtre, and heated along with fome wax: 
the magnet now attracted about 1 grain. 
The remainder weighed 3 grains, and 
confided of argil and filex. 
(h) To the folution of the metallic part 
was added fixed vegetable alkali: the preci¬ 
pitate was of a greyifh green colour, and af¬ 
ter having been edulcorated and dried, was 
difiolved again in marine acid, diluted 
with 2 parts of water, and a cylinder 
made of pure tin, which weighed 217 
grains, was put into the folution. The 
copper contained in the folution was pre¬ 
cipitated in a metallic date. The folu¬ 
tion began to lofe its green colour from 
below, till at lad all the copper being 
precipitated, it appeared without any co- 
jour. 
(cj The copper weighed 44 grains. In 
order to try the purity ol it, it was di- 
geded with heat in nitrous acid. The 
£ folution 
4 
