on the Compaction of James’s Powder, 321 
turned milky as before, or depofited a fediment ; therefore, 
this milkinefs depended on cold water diftolving a fmall'er 
proportion of James’s Powder than hot water. The whole of 
the filtered rnilky liquor was poured upon a filter as before, 
through which it paffed without any diminution of its turbid 
appearance ; and, on drying, the filter was found to have in- 
creafed only a quarter of a grain in weight. Some of the 
vapour that arofe during the ebullition being condenfed was 
found to be pure water. 
On a repetition of this experiment the phamomena above 
related were always obferved ; but the femi-vitrified James’s 
Powder above-mentioned (/) afforded a much lefs milky fluid 
and fediment than the powder ufed in the preceding experiment. 
In order to determine the kind of fubftances in water 
after boiling in it James’s Powder, the following re- agents 
were added to the above filtered liquor. 
1. Acid of fugar fometimes occafioned immediately more 
turbidnefs, and at other times tranfparency was inftantly pro- 
duced ; but in all cafes, on {landing, more fediment fell than 
from the filtered liquor alone. 
2 . Muriated barytes in about an hour rendered this liquid 
evidently more turbid, and on {landing more fediment was 
depofited than from the filtered liquid to which nothing had 
been added. 
3. Lime-water occafioned immediately a curdy appearance. 
4. Infufion of turnfole was fometimes turned to a flight 
red ; but in general It was not altered in colour. 
5. Nitre of filver produced in a few hours a flight fediment. 
6. Pruffianated alkali of tartar occafioned no alteration im- 
mediately, nor for four days after adding acetous acid to this 
mixture. 
Vol. LXXXI. U u 
7. Mild 
