production will in the future, as in the past, be absorbed locally. Most of the coal in the United States available for export is higher in volatile matter than the British and German export coal. This quality will in some degree be a limiting factor in exportation. On the other hand, it may result in wider introduction of briquetting, coking, and other processes, which will tend to improve the local industry and be conservational in their effect.
Japan will doubtless hold some of the Asiatic coal market gained during the war.
International coal relations are further discussed in Chapter XVIII.1
Production in the United States. The main features of the distribution of coal supplies in the United States are:
(1) Localization of the anthracite production and reserves in a limited area in the Lawton region of Pennsylvania. Low-grade anthracite coal also occurs in Rhode Island, North Carolina, Colorado, and Idaho.
(2) Localization of the bituminous production in the eastern and interior states of Pennsylvania, West Virginia, Ohio, Indiana, Illinois, and Kentucky. The principal reserves of bituminous coal occur in the same provinces, but important additional reserves are known in Texas, in North and South Carolina, and in the Rocky Mountain and Pacific Coast provinces.
(3) The existence of large tonnages of subbituminous coal in the west, which have not been mined to any extent.
(4) The existence of large fields of lignite in the Gulf Coast region, and in the Northern Plains region, which have not been mined.
Coke. About one-sixth of the bituminous coal mined in the United States is made into coke, that is, it is subjected to heat in ovens from which oxygen is excluded in order to drive off the volatile gases (chiefly hydrocarbons