1820.] the Composition of Chloride of Sulphur. ' 415 



tlble of being corrected by the application of more recently 

 discovered facts. Hence as far as the analysis of the chloride 

 goes, their researches are quite useless. Had I taken the 

 trouble to separate the chloride of silver from the sulphuret, and 

 had I recorded the weight of each in my original paper, my expe- 

 riments of 1803 might have been applied with ease to determine 

 the true composition of the chloride of sulphur which 1 at that 

 time subjected to analysis ; but the neglect of these essential 

 facts prevents the possibility of making any use of my experi- 

 ments, and of course renders it quite unnecessary to correct 

 them. 



I am of opinion that whenever sulphur and chlorine are 

 united together by my original process ; namely, by passing a 

 current of chlorine through flowers of sulphur till the whole is 

 liquified, we always form a subbichloride of sulphur, or a com- 

 pound of one atom chlorine with two atoms of sulphur. At 

 least I have repeated the process three times, and each time the 

 liquid formed was a subbichloride. I have not tried the effect of 

 continuing the current of chlorine gas as long as it continues to 

 be absorbed ; but it would probably form a chloride of sulphur, 

 or a compound of one atom chlorine and one atom sulphur. But 

 in the chloride of sulphur which I prepared and attempted to 

 analyze in 1803, the current of chlorine was continued a consi- 

 derable time after the sulphur Avas liquified. Hence there was 

 probably more chlorine in it than in the liquid, the analysis of 

 which has been related in this paper. This was probably the 

 reason why its specific gravity was different from that of the 

 liquid obtained by BerthoUet, and Bucholz, and from that which 

 I employed for the present analysis. BerthoUet, or at least 

 Bucholz, had prepared subbichlorides of sulphur ; while the 

 liquid on whicli my original experiments were made was proba- 

 bly a simple chloride. 



That a compound of one atom of chlorine and one atom of 

 sulphur exists as well as a subbichloride of sulphur, appears to 

 me sufficiently demonstrated from a synthetical experiment 

 related by Sir H. Davy. He found that when dry sulphur is put 

 into chlorine gas, the gas is absorbed by the sulphur, and a 

 liquid chloride formed. Now he observed that 10 grs. of sul- 

 phur were just capable of absorbing 30 cubic inches of chlorine 

 gas; but 30 cubic inches of chlorine gas weigh 22-876 grs. 

 According to this experiment, 10 grs. of sulphur combine with 

 22-87o grs. of chloiine ; of consequence, two grains of sulphur 

 would combine with 4'57o grs. of chlorine. Now 2 is the 

 weight of an atom of sulphur, and 4-o75 only exceeds the weight 

 of an atom of chlorine by 0-075 gr. An error of half a cubic 

 inch in the quantity of chlorine absorbed by the sulphur would 

 have produced this difference. I think, therefore, we may con- 

 clude, without any hesitation, that Davy's synthetical chloride 

 was a compound of one atom chlorine + one atom sulphur. 



