300 Mr. Ci-ienevix’s Enquiries concerning the Nature 
matrass was lined with a thin metallic coat. The liquor was 
passed through a filtre, which I had weighed; and the precipitate, 
after digestion with muriatic acid, was well washed and dried. 
When I had collected as much of this as I could, there remained 
upon the filtre 12 grains; besides which, I had collected 264, in 
all 276. The supernatant liquor still contained a portion of mer- 
cury, and about eight grains of platina Therefore, the 276 were 
composed of 92 of platina, and 184 of mercury. From this it ap- 
pears, that one hundred grains of platina, can determine the 
precipitation of near two hundred grains of mercury, by green 
sulphate of iron ; and that, in this proportion, there is a reciprocity 
of saturation. The 264, collected from the filtre, were exposed 
to a low red heat, and were reduced to 144. The 12 of the filtre 
would have given about seven ; therefore, the whole would have 
been 151. The substance was in the form of a fine powder, and 
had a metallic lustre. It was then put into a charcoal crucible, 
and fused into a button. This button weighed 128 grains, and, 
with the quantity left on the filtre, would have weighed 135. In 
this 135, there were 92 of platina ; therefore, it was composed of 
about two parts of that metal and one of mercury. It was of the 
specific gravity of 11,2 ; was wholly soluble in nitric acid; was 
easily fused by sulphur; was precipitated by green sulphate of 
iron : in a word, it was not to be distinguished from palladium. 
Exper. 2. As another mode of forming palladium in the 
humid way, I put metallic iron into a mixed solution of platina 
and mercury. Both metals were precipitated ; and the precipitate 
was submitted to the same treatment as in the former case ; but 
the success was not so complete. Iron can precipitate either 
platina or mercury separately ; but green sulphate of iron can 
perform its function only in favour of the affinity of platina and 
