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SELECTED ARTICLES. 
At the same time it is obvious that the phosphate of lime can 
have no other effect than that of increasing the bulk of the 
powder. In the course of his paper Mr. Chenevix mentions 
his having made an analysis of some specimens of James' 
powder, which he believes generally to contain about forty- 
four per cent, of peroxide of antimony, of which Dr. Pearson 
found about fifty-seven. Mr. Chenevix likewise gives his 
reasons for believing the ingredients of James' powder to be 
mechanically mixed, not chemically combined. The experi- 
ments of Berzelius on James' powder are mentioned casually 
in his system of chemistry. He states that he found about 
one per cent., to be soluble in water, and he regards it as an an- 
timonite of lime. The residue, he says, contains about two- 
thirds antimonious acid, and one-third phosphate of lime; this 
makes the proportion of peroxide of antimony about sixty-six 
per cent., which is higher a good deal than Dr. Pearson's. 
The Swedish chemist likewise regards the powder as being 
a mixture of its ingredients, not a chemical compound. 
The most recent observations bearing on this subject are 
some remarks by Mr. Richard Phillips, in the twentieth 
volume of the Annals of Philosophy, on the pulvis antimo- 
nialis of the Pharmacopoeia. This he regards as consisting 
of from thirty-five to thirty -eight per cent, of peroxide of an- 
timony, and from sixty-two to sixty-five of phosphate of lime. 
Mr. Phillips does not seem to have tried whether any part of 
the powder was soluble in water; and he did not believe 
that there was any protoxide (sesquioxide) of antimony in the 
portion dissolved in muriatic acid. He did not, however, 
employ as a test the sulphuretted hydrogen gas, which is the 
most certain method of detecting antimony in solution, and 
his other experiments on this point are not satisfactory. Mr. 
Phillips also regards the pulvis antimonialis as a mere mix- 
ture of its ingredients. 
It thus appears from these experiments that the general 
opinion with regard to both these preparations, is, that they 
consist of an insoluble oxide of antimony and of phosphate of 
