on the Compoftion of James’s Powder . 325 
(d) Salited barytes made it inftantly turbid. 
(*?) Alkalies, mild and cauftic, induced no change. 
(jf) Pruffian alkali produced only a clear greenifh colour,, 
after the addition of vinegar, and long Handing. 
(<§0 A very fmali quantity of marine acid rendered it quite 
clear; but it required much more nitrous acid to produce this 
effedt ; and this mixture did not whiten copper. 
(/6) With nitre of filver the filtered liquor turned of a 
fomewhat bluifh hue, and afterwards curdy. 
The undiflolved matter that remained on the filter, p. 324. 
1. 22. above mentioned, appeared, on examination, to be the fame 
kind of fub fiance, with a larger proportion of iron, as that 
which was diflblved by water, the experiments on which have 
been juft mentioned. In particular, it afforded Algaroth 
powder, but did not whiten, in the fmaileft degree, a copper 
plate. 
The following conclufions may, perhaps, be juftifiably 
drawn from thefe experiments on James’s Powder with 
water. 
1. That the whole, or a part, is foluble, or at leaft may be 
fufpended, in about 2000 times its weight of pure water cold; 
and in about half this quantity of boiling water. 
2. That this folution contains calcareous earth united to an 
acid, or fome other fubftance, from which it cannot be dif- 
united by cauftic or mild fixed alkalies ; therefore, the preci- 
pitation by muriated barytes cannot be referred to vitriolated 
lime. 
3. That this folution contains a metallic calx, a part of 
which at leaft is that of antimony uncombined, or at leaft not 
united to any acid with which it forms a compound foluble in 
water. 
4. That 
