g8o Mr. Chevenix’s Experiments and Observations 
solution , the water of the former would act upon the entire mass 
of oxide of antimony, while the alkali would precipitate the 
phosphate of lime only as it saturated the acid which held that 
salt in solution: thus, the precipitate would contain more anti- 
mony in the beginning ; and, towards the end, the phosphate of 
lime would be predominant. For the same reason too, a pure 
alkali is preferable to its carbonate ; for the carbonic acid disen- 
gaged, would retain in solution a portion of phosphate of lime. 
Whether this composition be a chymical combination or a 
mixture, I will not take upon me to determine; but, for the 
reasons above mentioned, in speaking of Dr. James’s Powder, 
I believe it to be merely a very intimate mixture. At all events, 
it must be more homogeneous than any that can be prepared in 
the dry way. It is entirely soluble in every acid that can dis- 
solve either phosphate of lime or oxide of antimony separately ; 
and, to have it constantly and uniformly the same, no further 
address in preparing it is required, than to avoid the errors I 
have mentioned. 
As, after some medical trials of the powder, it was suggested 
to me, that it might be advantageous to render it somewhat 
stronger, I prepared another portion, by taking two parts of 
oxide of antimony and but one of phosphate of lime, and pre- 
cipitating as above described. The medicinal power was then 
considerably increased. 
Dr. James’s Powder is a medicine which has been so long in 
use, and is so deservedly ranked among the most valuable we 
possess, that every attempt to render the process for preparing 
it more simple and more certain, must be allowed to be of some 
importance. But, whatever reason there was to think, by ar- 
guing upon its chymical properties, that I had really succeeded 
