PREPARED BY THE EDITORIAL STAFF OF THE MENTOR ASSOCIATION
ILLUSTRATION FOR THE MENTOR. VOL. 6, No. 6, SERIAL No. 154
COPYRIGHT, 1918. BY THE MENTOR ASSOCIATION, INC.
COURTESY POPULAR SCIENCE MONTHLY
CHARGING COAL IN A MODERN GAS PLANT
THE STORY OF COAL
Coal Products
FOUR
The story of the coal products forms one of the most romantic chapters in the history of applied science. The marvels of fairyland are surpassed by the achievements of the modern manufacturer in obtaining from mere black rocks dug out of the ground not only heat and light, but a bewildering variety of useful gases, liquids and solids—drugs, chemicals, dyestuffs, and so forth.
For hundreds of years it has been known that when coal is covered or enclosed, to keep out the air, and then heated for a certain length of time, instead of burning to ash it is converted into a porous grayish-black substance called “coke.” This material, which burns without smoke or flame, is a valuable fuel for many purposes; especially for use in blast-furnaces for the smelting of ore. Nowadays coke is made on a vast scale from certain grades of bituminous and semi-bituminous coal. The coal is heated in “coking-ovens,” of which there are several kinds. The most common form of oven in this country is the “bee-hive oven,” which produces coke only. Another type of coking-oven, more generally used in Europe than in America, is the “flue-oven,” which produces, besides coke, a number of valuable by-products.