Comhustihle Mineral of the Mersey River. 1 1 1 



ingly, as a gas-yielding material, it is very inferior to 

 ordinary cannel coal. 



The coke from it is utterly worthless. It consists almost 

 entirely of clay and sand, and a very small quantity only of 

 combustible matter, or " fixed carbon." The following 

 Table shows the per-centage amount of coke afforded by this 

 mineral and by the coals previously referred to, and also 

 the proportion of " fixed carbon " and ash in each coke : — 





Coke from 



Fixed Carbon 

 in Coke. 



Ash in 



Coke. 



Tasmanian Mineral 



per cent. 

 76-70 



41-07 



31-52 



per cent. 

 717 



89-50 



33-38 



per cent. 

 92-83 



Lesmahago Gas Coal 



Boghead Gas Coal 



10-50 

 66-62 







In estimating the value of coal for the manufacture of 

 gas, the quality of the coke which is used as fuel ift the 

 distillation of the coal, and also sold for other purposes, is 

 an important item of consideration. The heat-producing 

 powers of coke, when used as fuel, depend exclusively on 

 the " fixed carbon," or charcoal, it contains, and accordingly 

 its economic value is directly proportioned to the amount of 

 this ingredient. In the coke from Lesmahago coal, there is 

 a large per-centage of " fixed carbon," and it is therefore 

 very valuable as fuel. Boghead coke, on the contrary, is 

 very deficient in this respect, and almost valueless. The 

 product from the present mineral is little else, as already 

 mentioned, than clay and sand, (nearly 93 per cent.), and 

 scarcely entitled therefore to the name of coke. 



I made a careful analysis of the ash which this mineral 



