THE ACTION OF ORGANIC SULPHUR IN COAL. McCALLUM. 213 



i^ot knowing in what state of combination the organic 

 sulphur occurs in coal, it is impossible to say what effect the 

 heat of the coke oven will have. It was, as previously stated, 

 in an attempt to throw some light on this question, that the 

 investigation was undertaken. 



Now to return to our coal samples. The only way o 

 obtain such a series of samples as previously mentioned, viz. : 

 with decreasing inorganic and increasing organic sulphur was 

 to fractionate the coal on the basis of specific gi'avity, that is 

 separate it into several fractions of gradually decreasing specific 

 gravity. The means used to accomplish this were solutions of 

 calcium chloride of viarying specific gravities. The coal used 

 was crushed to pass through iV inch mesh screen and was 

 then placed in a vessel containing a solution of calcium chloride 

 of slightly higher specific gravity than that of the coal. 



For instance, the raw coal was found to have a specific 

 gravity of 1.323. For this a calcium chloride solution of 1.35 

 specific gravity was used. This separated the coal into two 

 fractions having the following specific gravities : the lighter 

 material 1.275, and the heavier 1.731. 



Part of this lighter or floating fraction was reserved for 

 analysis and the remainder was treated with a calcium chloride 

 solution of lower specific gravity. This procedure was kept 

 up imtil, at a specific gravity of 1.24, there was no floating 

 fraction. 



Between these two extremes I obtained five fractions of the 

 following respective specific gravities : 



Xo. 1 1.323 



:N'o. 2 1.275 



Xo. 3 1.2()1 



'No. 4 1.253 



No. 5 1.243 



