In the ‘Bul. Soc. Chim.,’ vii, 274, several reactions by which anthracene is formed are described by Berthelot, as by the action of heat on other hydrocarbons, or by passing the vapours of ethylene, styrolene, and benzene through a porcelain tube heated to bright redness.
A great number of products are procured from anthracene, by far the most important of these being artificial alizarin.
See Alizarin, Artificial.
AN′THRACITE (sīte). [Eng., Fr.] Syn. Anthrac′olite, Glance′-coal, Stone′-coal‡, Mineral char′coal*; Anthraci′tes, L.; Glanzkohle, Ger. A species of coal found in the transition-rock formation, consisting chiefly of dense carbon. It has a conchoidal fracture, a semi-metallic lustre, and a sp. gr. usually varying from 1·4 to 1·6. It burns without either flame or smoke, emits an intense heat, and leaves scarcely any ash; but it is difficult to kindle, and requires a lively draught for its combustion. It is the common fuel in the United States of America, although, until recently, scarcely employed in Europe, and that chiefly in a few iron works and steam furnaces. Its adoption in this country would not merely at once remove the smoke nuisance, but would produce a vast annual saving to the community. By contracting the throat of the chimney a little, and avoiding the use of the poker, it may be burnt in a common grate. The Americans use a little charcoal as kindle, and seldom supply fresh coal to the fire oftener than once or twice a day.
The inferior varieties of anthracite are technically and provincially called culm; as is also the small and waste of the better kinds.
For the analysis, geology, calorific value, &c., of anthracite, see Coal, Culm, Evaporation, Fuel, Heat, &c.
De la Beche describes Anthracite as “a variety of coal containing a larger proportion of carbon, and less bituminous matter, than common coal.”
In the ‘Memoirs of the Geological Survey’ we read:—“We see the same series of coal beds becoming so altered in their horizontal
range that a set of beds bituminous in one locality is observed gradually to change into anthracitic in another. Taking the coal measures of South Wales and Monmouthshire, we have a series of accumulations in which the coal-beds become not only more anthracitic toward the west, but also exhibit this change in a plane which may be considered as dipping south-south-east, at a moderate angle, the amount of which is not yet clearly ascertained, so that in the natural sections afforded, we have bituminous coals in the high grounds and anthracite coals beneath. This fact is readily observed either in the Neath or Swansea valleys, where we have bituminous coals on the south and anthracite on the north; and more bituminous coal-beds on the heights than beneath, some distance up these valleys, those of the Nedd and Tawe. Though the terms bituminous coal and anthracite, have been applied to marked differences, the changes are that there is no sudden modification to be seen. To some of the intermediate kinds the term “free burning” has been given, and thus three chief differences have been recognised.”
The term Culm is applied both to an inferior kind of anthracite only worked for lime-making and mixing with clay and to the small pieces of anthracite obtained in working the beds of true anthracite. It is also known under the names of Blind-coal, Glance-coal, and Kilkenny-coal.