366 Dr. Pearson’s Experiments and Obfervations 
Antimony* Sulphur. Air. 
1200 — 300 -j- 100 = 1000 Antimonial calx. 
Calcar. Aerial Vitriolic 
earth. acid. acid. 
8°° — 300 450 = 950 Vitriolic felenite. 
1 95 ° 
Lofs by fublimation and walte 150 
1800 
With regard to the nature of this calx, the greateft part of 
it readily diflolved in marine acid ; and part of what then re- 
mained was alfo diflolved, but with great difficulty and very 
fparingly ; a minute quantity refilled folution entirely. 
exp. xii. 600 grains of coarfely powdered antimony were 
mixed with 400 grains of purified white fand, and calcined as 
in making Lile’s Powder. The fmell of fulphur continued 
for one hour and a half, and the mixture was calcined for half 
an hour longer. On cooling, a brown powder was obtained 
which weighed 820 grains, and expofed to ico° of fire, melted 
into an irregularly figured, blackiffi mafs, full of cavities. 
In this experiment the lofs of weight correfponds nearly to 
that in experiments above related, viz. thole in which the 
deficiency of weight after calcining antimony alone was about 
29! per cent. The much longer time required in this experi- 
ment for carrying off the fulphur than in the calcinations with 
bone- allies, gypfum, and chalk, perhaps is owing to there 
being no affinity between antimonial calx and filiceous earth. 
I beg leave to mention one more experiment relative to 
James’s Powder. 
exp. xni: A medicine is fold by F. Newbeky, under the title 
of “ James’s Powder for Horfes, Horned Cattle, Hounds, &c.” 
It is a light clay-coloured, gritty, tallelefs fubltance, in which 
are 
