100 iWf. jR. Phillips on James*$ Potvder, [Septi 



the Pharmacopoeia in containing about one half more peroxide 

 of antimony ; but as it is questionable whether phosphate of 

 lime is not as active as this peroxide, the difference of composi- 

 tion, though great in figures, can be but httle in fact. When I 

 allude to the composition of the pulvis antimonialis, it is of 

 course to be understood that I speak of the result of my own 

 analysis ; but I shall presently adduce authority to show, that 

 instead of being merely an inert preparation, it possesses the 

 greater inconvenience of extreme uncertainty. 



I cannot close this account of James's powder without allud- 

 ing to some remarks which Dr. Paris has made in the last edition 

 of his Pharmacologia (vol. ii. p. 357), upon my analysis of the 

 pulvis antimonialis ; and I hope the reader will excuse my quot- 

 ing the observations at length. 



*' While correcting the present sheet for the press, a paper 

 has appeared in the Ammls of Philosophy for October, 1822, by 

 Mr. Richard Phillips, of too important a character to be passed 

 over without notice, as not only raising a question with respect 

 to the chemical composition of this powder, but with regard to 

 its medicinal efficacy. 



** In consequence of the antimonial powder having proved 

 inert in the hands of Dr. Elliotson, although exhibited to the 

 amount of 100 grains for a dose, Mr. PhilHps was induced to 

 examine more particularly into the nature of the oxide which 

 enters into its composition. * After the well established fact,' 

 says he, * that peroxide of antimony is nearly or totally inert, it 

 appears to me, that if proof could be obtained, that the oxide of 

 antimony is in this state, the deficiency of power in the pulvis 

 antimonialis would be accounted for.' He then proceeds to 

 detail his experiments, from which he deduces the composition 

 of this preparation to be as follows : 



Peroxide of antimony 35 



Phosphate of hme • . QS 



100 



which exist together in a simple state of mixture. Until the 

 subject be elucidated by further experiments, it will be difficult 

 for the chemist to persuade the physician, that he can never 

 have derived any benefit from the exhibition of antimonial 

 powder." 



For additional evidence as to the nature of this preparation, I 

 beg to refer Dr. Paris to a statement respecting it, which has 

 been made by Mr. Brande, and which, if I had remembered, 

 would have saved me the trouble of an analysis. " In examining," 

 says Mr. Brande, " the antimonial powder from various sources 

 prepared according to the direction of the Pharmacopoeia, 1 

 have found it of very variable composition : sometimes it con- 

 tains peroxide of antimony only ; sometimes there is a propor- 

 tion of protoxide, and, in some few cases, the powder has con- 



