1814.] On the Composition of Sulphuret of Antimony. 99 



The watery liquid thus freed from the antimony, s ,; ll contained 

 a considerable portion of sulphur, which had been acidified by the 

 action of the nitric acid. Accordingly, when muriate of barvtes 

 Was dropt in, a copious precipitate of sulphate of barytes fell. 

 This precipitate, when washed and dried, weighed 1193 grains; 

 equivalent to 40C>J grains of sulphuric acid, or to 16'23 grains of 

 sulphur. 



From the preceding analysis it appears that 100 parts of sul- 

 phuret of antimony contain 26*23 parts of sulphur: therefore, the 

 sulphuret in question is composed of 



Antimony 73*77 100-000 



Sulphur 26*23' 35-556 



This result approaches most nearly to the analysis of Bergman. 

 The reader will observe too, that it almost coincides with the mean 

 of all the preceding analyses, if we leave out that of Wenzel. It 

 was this circumstance that gave me confidence in it, and induced 

 me to consider it as approaching more nearly to precision, than. any 

 of the analyses offered to the public by preceding chemists. 



Let us suppose then that sulphuret of antimony is composed as 

 I have just stated; and let us deduce from -that composition the 

 weight of an atom of antimony. If we suppose, as 1 have done 

 (Annals of Philosophy, ii. 1 12) that this sulphuret is a compound 

 of two atoms sulphur and one atom antimony, we have this ana- 

 logy, 35*556 : 1U0 :: 4 : an atom of antimony. This would give 

 us the weight of an atom of antimony 11249. This is a very 

 little more than 1 originally made it in my first table, deduced from 

 the analysis of the oxides of antimony ; analyses attended with »o 

 much difficulty, that implicit confidence could not be put in them. 



The 935 grains of white oxide of antimony, obtained in the 

 preceding analysis, obviously contained 19 - 73 grains of oxygen ; 

 so that this oxide of antimony is composed of 100 metal + 26*745 

 oxygen. This is the oxide which Bcrzelius has distinguished by 

 the name of antimonious acid. For when heated to redness in a 

 platinum crucible, it becomes of a dazzling whiteness, and exhibits 

 the other properties of that substance which be has described. My 

 analysis of it agrees nearly with the previous analysis of it by Mr. 

 .John Davy, who found it a compound of 100 metal + -6-l;l 

 oxygen. Now if we suppose it a compound of one atom metal 

 and three atoms oxygen, which was the original supposition that I 

 let out with in my first table, we shall find that this very nearly 

 coincides with the above analysis: for 1 1*549 : 3 :: 100 : 26 669. 

 Now this differs very little from the result of my . a ysis. If we 

 were to consider the Analysis of the oxides o inony by fler- 



Eelius, in hi- paper <>u the Cause of (.'hen op rtions, pub- 



lished in the preceding volume of the /ar,. Philosophy, as 



• ei, Hie weight of an atom of antimony would he 16* 129. 

 I must , that several of his conclusioi seem to me 



fouiiJcd upon too slender analogies to be entitled to confidence. I 



G 2 



