378 Mr. Phillips's Analysts ofTartarized Antimony, [Ma*, 



which supposition I ought to have obtained 53-05 of precipitate 

 instead of 52-8; and it will be observed that supposing this to be 

 the true constitution of this substance, the results of B will agree 

 with those of C as nearly as 43-46 to 44*04, for subhydrosul- 

 phuret of antimony must consist of 52 x 2 + 17 = 121, and 

 121 : 104 :: 51-2o : 44-04. 



E. Further to examine this view of the subject, I dissolved 

 100 o-rains of sulphuret of antimony and 100 grains of the pre- 

 cipitate in question in separate and equal quantities of muriatic 

 acid, and decomposed the solutions with similar portions of 

 water; the precipitate from the sulphuret weighed 86-7 grains, 

 and that from the hydrosulphuret 87 grains ; and as in 1 atom of 

 subhydrosiilphuret, 17 of sulphuretted hydrogen, and 16 of 

 oxygen = 33, would supply the place of 2 atoms of sulphur=32 

 in 2 atoms of sulphuret of antimony, it is evident that equal 

 weights of these cumpounds, should yield nearly equal quantities 

 of precipitate by solution in muriatic acid and the affusion of 

 water. 



F. The nature of this precipitate was then examined by heat- 

 ino- 50 grains in a small flask by a spirit-lamp, and I found to 

 my surprise, that it was readily converted into black sulphuret 

 of antimony, losing only 1-2 grain of water. It appears, there- 

 fore, that instead of a subhydrosulphuret as I had suspected, the 

 precipitate was sulphuret, containing a small quantity of hydro- 

 sulphuret, but yet sufficient to give so much colour as to conceal 

 the nature of the sulphuret. The difficulty of the case was 

 increased by the fact already alluded to, viz. that 2 atoms of 

 oxygen and 1 atom of sulphuretted hydrogen are so nearly equal 

 in weight. 



G. As then 50 of the precipitate contain 48-8 of sulphuret of 

 antimony, 51-25 the whole quantity obtained, (C) must contain 

 50-02 = 43-35 of protoxide of antimony, which is the quantity 

 contained in 100 grains of crystallized emetic tartar. 



We have thus obtained 7-4 as the quantity of water, and 43-35 

 as the weight of the protoxide of antimony ; and having found, 

 as already mentioned, that crystals of tartarized antimony are 

 obtained even from the last portions of the solution in preparing 

 the salt, the remainder of 49-25 vvill give the weight of the bitar- 

 trate of potash in 100 parts, or it consists of 



Bitartrate of potash (anhydrous) .... 49-25 



Protoxide of antimony 43-35 



Water 7-40 



100-00 



Calculating its constitution, according to the weight of the 

 atoms already mentioned, tartarized antimony will appear to b« 

 a compound of 



