It is a species of cannel coal, somewhat similar to the Boghead mineral of Scotland, but yielding a much larger percentage of volatile hydro-carbon than the Scottish mineral.
The word "kennel," a gutter, a drain in a street or road, is a corruption of the Middle English canel, cannel, in modern English "channel," from Latin canalis, canal.
Lignite and cannel are usually dull and earthy, and of an irregular fracture, the latter being much tougher than the black coal.
Some lignites are, however, quite as brilliant as anthracite; cannel and jet may be turned in the lathe, and are susceptible of taking a brilliant polish.
This excess is greatest in what is Gas known as cannel coal, the Lancashire kennel or candle coal, so named from the bright light it gives out when burning.
Cannel is more compact and duller than ordinary coal, and can be wrought in the lathe and polished.
These properties are most highly developed in the substance known as jet, which is a variety of cannel found in the lower oolitic strata of Yorkshire, and is almost entirely used for ornamental purposes, the whole quantity produced near Whitby, together with a further supply from Spain, being manufactured into articles of jewellery at that town.
In cannel coals the prevailing constituents are the spores of cryptogamic plants, algae being rare or in many cases absent.
Cannel coals are generally variable in quality, being liable to change into shales or black-band ironstones within very short horizontal limits.
The use of this machine has allowed a thin seam of cannel, from 10 to 14 in.
Of cannel coal Kentucky is the largest producer in the Union, its output for 1902 being 65,317 short tons, and, according to state reports, for 1903, 72,856 tons (of which 46,314 tons were from Morgan county), and for 1904, 68,400 tons (of which 52,492 tons were from Morgan county); according to the Mineral Resources of the United States for 1907 (published by the United States Geological Survey) the production of Kentucky in 1907 of cannel coal (including 4650 tons of semi-cannel coal) was 77,733 tons, and exclusive of semi-cannel coal the output of Kentucky was much larger than that of any other state.
Formerly cannel coal was used for Enrich- producing a very rich gas which could be mixed with the meat.