158 STONE COAL. BOVEY COAL, &C. 
stances been sold as jet (222). Of all the kinds of coal 
that are used for gas-lights, none are said to be so use- 
ful as this. 
220. STONE COAL, KILKENNY COAL, WELSH 
COAL, or GLANCE COAL, is of a dark iron-black colour, 
with a metallic lustre and foliated texture ; and consists almost 
entirely of charcoal. 
Unlike most other kinds of coal, this occurs both in 
stratified masses, and in lumps, nested in clay. It is 
found in several countries of the Continent, in Wales, 
Scotland, and near Kilkenny in Ireland. 
When laid on burning coals, it becomes red hot, emits 
a blue lambent flame in the same manner as charcoal ; 
and is, at length, slowly consumed, leaving behind a 
portion of red ashes. No smoke nor soot is produced 
from this coal; but, on the contrary, it whitens the 
places where the fume is condensed ; and the effluvia 
which it gives out are extremely suffocating. 
This coal is chiefly used in the drying of malt. 
221. BOVEY COAL, BROWN COAL, or BITU- 
MINOUS WOOD, is of brown colour, and in, shape exactly 
resembles the stems and branches of trees, but is usually com- 
presse'd. It is soft, somewhat flexible, and so light as nearly to 
float when thrown into water. 
The greatest abundance of this coal occurs at Bovey, 
near Exeter, from which place it derives its name. The 
lowest stratum is worked at the depth of seventy- five 
feet beneath the surface of the earth. It is also found 
in Scotland, Ireland, and Germany. 
As fuel, the Bovey coal is used only by the poorest 
classes of the community, as, notwithstanding its burn- 
ing with a clear flame, it emits a sweetish but extreme- 
ly disagreeable sulphureous gas, which is injurious to 
the health of the inhabitants. It is principally used for 
the burning of lime, and for the first baking of earthen 
ware. 
222. JET, or PITCH COAL, is a solid, black, and 
opaque mineral, harder than coal, and found in detached 
