FROM DIFFERENT KINDS OF COAL.

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yellowish white blaze, which do not swell or cakeon the fire, and require no stirring, which produceno slag, and by a single combustion are reduced tolight white ashes. Some of this species of coalwhen suddenly heated crackle and split into pieces,especially if laid on the fire in the direction of thecross fracture of their laminae.

Cannel coal, deserves to be placed at the head ofthis class; next to this, we may rank all thosedescriptions of coal known in the London marketby the names of Hartley, C'owpers Main, TanfieldMoor, Eighton Main, Blythe, and Pont Tops. Italso includes the sort of coals found in several partsof Scotland , called Splent coal, and some of thoseraised on the Western Coast of England.

Most of thecoals raised in Staffordshire ought like-wise to be classed among this species of coal, but theline of distinction between these, and the classessubsequently named, cannot be accurately drawn.

The following table exhibits the maximumquantity of gas obtainable from the first class ofcoal.*

* Own Experiments, made at the Royal Mint Gas-Works.