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SELECTED ARTICLES. 
of lime, the quantity of sulphuret which it yielded being only 
0.3 grain, and the phosphoric acid being indicated in much 
larger quantity. 
On making a set of comparative experiments with pulvis 
antimoniulis, I found it to correspond in composition with 
the true James' powder, but, like the patent medicine, to 
vary very much in the proportion of its ingredients. Thus 
in one specimen I found only 0.8 grains soluble in water, the 
sesquioxide amounted only to 3.98, the antimonious acid 
was 50.09, or rather more than one-half of the whole, and the 
phosphate of lime indicated by oxalate of ammonia corres- 
ponded within a few tenths of a grain to the remainder of the 
100 parts. It would therefore seem from these experiments, 
that both James' powder and its imitation contain a propor- 
tion of antimony in a soluble and therefore active state; that 
this proportion varies very much, being in the James' pow- 
der sometimes equal to more than nine per cent., at other 
times less than three. 
Mr. Phillips' experiments, by which he satisfied himself that 
there was no sesquioxide present, at least in the pulvis an- 
timonialis, appear a priori to be inconclusive, and the above 
experiments prove, I think, that he was mistaken. He in- 
ferred that the muriatic solution contained none of this oxide, 
because, like the common muriate of antimony, it did not let 
fall any precipitate on diluting it with water. Had he em- 
ployed the sulphuretted hydrogen he would have been set 
right on this point. I find that this oxide, as contained in 
James' powder, does not require for its solution that the mu- 
riatic acid should be either concentrated or boiling, but that 
it will take it up at common temperatures, and when diluted 
with three times its bulk of water. 
It is certainly a curious circumstance, that in a preparation 
which has been exposed to a red heat, we should find any ses- 
quioxide of antimony, which is well known at such tempe- 
ratures to be converted into antimonious acid. May it not 
be that a certain proportion of it is combined with part of the 
