412 Dr. Thomson on [June, 



The ammoniacal solution of chloride of silver, being saturated 

 with muriatic acid, let fall the chloride of silver which it con- 

 tained. This chloride, being well washed and dried, was found 

 to weigh 83*7 grs. ; but as chloride of silver is a compound of 

 4*5 chlorine + 13*75 silver, it is obvious that 83*7 grs. of it 

 contain 20*63 grs. of chlorine. This of course is the quantity of 

 chlorine contained in the 42*9 grs. of the chloride of sulphur 

 subjected to analysis. 



From the preceding details, it is obvious that the chloride of 

 sulphur was composed of 



Chlorine 20*63 48*09 



Sulphur 19*67 45*85 



40*30 

 Loss 2*60 6*06 



42*90 100*00 



The loss of six per cent, incurred during this analysis will not 

 perhaps be thought excessive, if the length of time which the 

 analysis took up, and the volatile nature of the chloride of sul- 

 phur, be considered. It is probable that the greatest part of this 

 loss was owing to the escape of a portion of the muriatic acid 

 into which the chlorine was converted by agitating the chloride 

 of sulphur with water. Let us now see what inferences respect- 

 ing the constitution of chloride of sulphur we are entitled to 

 draw from the preceding analysis. An atom of sulphur weighs 

 2, and an atom of chlorine, 4*5. Hence it is obvious that our 

 chloride of sulphur was not a compound of one atom sulphur + 

 one atom chlorine ; otherwise the chlorine, instead of merely 

 exceeding the sulphur a little in quantity, would have been more 

 than double its weight. If we suppose the chloride examined to 

 have been a compound of two atoms sulphur + one atom chlo- 

 rine, then the weights of the sulphur and chlorine would be to 

 each other as 4 to 4*5 ; but 4 : 4*5 :: 45*85 : 51*68. Therefore, 

 if the quantity of chlorine obtained in the preceding analysis had 

 been 51*58 instead of 48*09, tiie chloride would have been com- 

 posed exactly of two atoms sulphur + one atom chlorine. Now 

 I have little doubt that from the greater volatihty of the chlorine 

 when compared to the sulphur, the greater part of the loss would 

 be owing to the escape of it, or of (he muriatic acid gas, into 

 which it was converted. I conceive myself, therefore, entitled 

 to conclude that the chloride of sulphur which I subjected to 

 analysis was a compound of two atoms sulphur + one atom 

 chlorine. It was, therefore, a subbichloride of sulphur. 



It is scarcely necessary to say that I repeated the preceding 

 analysis a second time without coming any nearer the truth. 

 I conceive it, therefore, quite unnecessary to state the details of 

 the other analysis. It was conducted precisely in the same way 



