upon Dr. James's Powder. 379 
powder in question is, in any degree, what M. Berthollet 
would call an antimoniate of lime. 
But, be the state, whether of mixture or of combination, what 
it may, my purpose is to endeavour to produce a substance, 
which, from its more certain mode of preparation, may be more 
equal and constant in its effects. 
Dissolve, together or separately, in the least possible portion 
of muriatic acid, equal parts of the forementioned white oxide 
of antimony and of phosphate of lime. * Pour this solution gra- 
dually into distilled water, previously alkalizated by a sufficient 
quantity of ammonia. A white and abundant precipitate will 
take place, which, well washed and dried, is the substitute I pro- 
pose for Dr. James's Powder. 
The theory of this precipitation is so clear and simple, that 
it does not require any comment. It may be useful, however, 
to those who wish to make this preparation, to remark, that 
it is absolutely necessary that the solution of phosphate of 
lime and of oxide of antimony, in muriatic acid, should, after 
being well mixed, be poured into the alkaline liquor , in order 
to obtain a precipitate homogeneous throughout the opera- 
tion. For, should the alkaline liquor be poured into the acid 
* In order to procure the phosphate of lime, I dissolved in muriatic acid, a quantity 
of calcined bone, and precipitated by ammonia, in its state of greatest causticity. By 
this means, the excess of muriatic acid, which held in solution the phosphate of lime, 
is saturated, and the phosphate is precipitated ; but no muriate of lime is decomposed, 
if the ammonia is quite free from carbonic acid. This is the most direct method of 
obtaining phosphate of lime pure. This salt is not decomposed, as some have asserted, 
by muriatic .acid; but merely dissolved by it. I have been induced to state fully these 
particulars, because, from the beneficial effects of this salt in the treatment of rachitis, 
as proposed by M. Bo n ho m me, ( Annates de Chimie, Vol. XVIII. p. 1 13,) it may be- 
come of general use. The oxide of antimony, I obtained by precipitating, by water, 
the common butter of antimony of the shops. 
3 C 2 
