Comhustihle Mineral of the Mersey River. 109 



smoke. The sand and clay are left as a bulky reddish 

 coloured ash. 



When distilled in a closed vessel, or retort, at a tempera- 

 ture below a red heat, it yields an oil, a strong acid, and 

 tarry matter, leaving a carbonaceous residuum in the retort. 

 The volatile products are of course derived exclusively 

 from the resinous ingredient. The quantity of mineral 

 received for examination was too small to admit of an 

 extended investigation being made into the exact nature of 

 the liquid products afforded by distillation. Even if there 

 had been sufl&cient for the purpose, I should not have con- 

 sidered it necessary to incur the expense of pursuing this 

 part of the inquiry, for, although exceedingly interesting in 

 a scientific point of view, it appears to me to be altogether 

 irrelevant to the principal questions submitted for my con- 

 sideration, viz., — Whether this mineral can be employed in 

 the manufacture of gas, or be applied to steam purposes, or 

 to any other practical use in the arts ? 



I have tried its gas-producing powers very carefully. 

 When strongly and quickly heated, in the same way that 

 coal is treated in the manufacture of gas, it affords a notable 

 quantity of gas, which is similar in qualities and powers to 

 that obtained from cannel coal. In consequence, however, 

 of the very large proportion of earthy matter existing in it, 

 the amount of gas that it gives is very small, as compared 

 with the quantity afforded by Scotch and English gas coal. 

 From a careful trial on a limited scale, I estimate that a 

 ton of the mineral will produce about 3000 cubic feet of 

 gas, which is a little more than one-fourth of the quantity 

 yielded by good cannel coal of this country. Lesmahago 

 coal, which is, with the exception of Boghead coal, the 

 most productive cannel coal in Scotland, gives about 11,500 



