ised from the mine is passed through breakers with
toothed rolls to reduce the lumps to smaller pieces, which are separated
into different sizes by a system of graduated sieves, placed in
descending order. Each size can be perfectly well burnt alone on an
appropriate grate, if kept free from larger or smaller admixtures. The
common American classification is as follows:--

Lump, steamboat, egg and stove coals, the latter in two or three sizes,
all three being above 1-1/2 in. size on round-hole screens.

Chestnut below 1-1/2 inch above 7/8 inch.
Pea " 7/8 " " 9/16 "
Buckwheat " 9/16 " " 3/8 "
Rice " 3/8 " " 3/16 "
Barley " 3/16 " " 3/32 "

From the pea size downwards the principal use is for steam purposes. In
South Wales a less elaborate classification is adopted; but great care
is exercised in hand-picking and cleaning the coal from included
particles of pyrites in the higher qualities known as best malting
coals, which are used for kiln-drying malt and hops.

Formerly, anthracite was largely used, both in America and South Wales,
as blast-furnace fuel for iron smelting, but for this purpose it has
been largely superseded by coke in the former country and entirely in
the latter. An important application has, however, been developed in the
extended use of internal combustion motors driven by the so-called
"mixed," "poor," "semi-water" or "Dowson gas" produced by the
gasification of anthracite with air and a small proportion of steam.
This is probably the most economical method of obtaining power known;
with an engine as small as 15 horse-power the expenditure of fuel is at
the rate of only 1 lb per horse-power hour, and with larger engines it
is proportionately less. Large quantities of anthracite for power
purposes are now exported from South Wales to France, Switzerland and
parts of Germany. (H. B.)

ANTHRACOTHERIUM ("coal-animal," so called from the fact of the remains
first described having been obtained from the Tertiary lignite-beds of
Europe), a genus of extinct artiodactyle ungulate mammals, characterized
by having 44 teeth, with five semi-crescentic cusps on the crowns of the
upper molars. In many respects, especially the form of the lower jaw,
_Anthracotherium_, which is of Oligocene and Miocene age in Europe, and
typifies the family _Anthracotheriidae_, is allied to the hippopotamus,
of wh