472 Proceedings of Philosophical SGcieiies. [June, 



phur contains carbon. It is in facta compound of carbon and 

 sulphur, and may therefore with propriety be called sidpliuret of 

 carhon. 



The last object was to determine the proportion of carbon 

 present in this compound. A great variety of methods were 

 tried^ such as burning in oxygen gas, decomposhion in alkalies, 

 &c. ; but none of them were found to answer. At last they 

 Kucceeded, by passing the sulphuret of carbon very slowly 

 through a red-hot tube filled with red oxide of iron. The 

 gaseous products were received over mercury. The red oxide of 

 iron was partly converted into sulphuret. To determine the 

 quantity of sulphur present it was dissolved in nitromuriatic acid, 

 and the whole sulphur converted into sulphuric acid. This acid 

 was thrown down by barytes, and its quantity accurately ascer- 

 tained. The gases over mercury were found to be a mixture of 

 sulphurous acid and carbonic acid. The sulphurous acid was 

 absorbed by brown oxide of lead, which by that means was con- 

 verted into sulphate; and the additional weight being ascer- 

 tained, determined the proportion of sulphurous acid present in 

 the gas. The carbonic acid was absorbed by potash, and its 

 weight determined in the same manner. From these data it was 

 possible to determine the proportion of sulphur and carbon pre- 

 sent in the alcohol of sulpliur. The result was that it is a com- 

 pound of 



Sulphur .......... 84-83 



Carbon 15-17 



100 



or of two atoms of sulphur and one of carbon. 



On Thursday the 13th of May an appendix to the preceding 

 paper, by Professor Berzeiius, was read. It consisted of the 

 four following particulars : — 



1. An account of the method employed in determining the 

 proportions of carbon and sulphur in the sulphuret of carbon. 

 The mode was to decompose a given weight of sulphuret of 

 carbon by passing it through red-hot peroxide of iron, and re- 

 ceiving the products over mercury. The sulphuret of i>on 

 formed was dissolved, and the sulphur converted into sulphuric 

 acid. The weight of sulphuric acid, of sulphurous acid, and of 

 carbonic acid, formed, was ascertained; and from the known 

 composition of these three substances the proportion of carbon 

 and sulphur was determined. Two experiments were made. In 

 the first the loss amounted to id of a per cent. ; in the second 

 to eight thousandth parts. 



2. Some observations on the atomic theory. According to 

 Mr. Dalton's theory, sulphuret of carbon is a compound of two 

 atoms of sulphur and one pf carbon. Professor Berzelius makes 



