Of the contents of the blast furnace by far the larger bulk is fuel, though the weight of the iron ore is almost twice that of the fuel. The square columns in our illustration will serve to give one some idea of the amount of fuel which was consumed in 1902 by the blast furnaces of the United States. A fair estimate would be about 16,000,000 tons of coke, 1.600,-000 tons of coal, and 300,000 tons of charcoal. Coke is so light that if the 16,000,000 tons were built up in a column 400 feet square, the column would reach an altitude of 6,500 feet. No human monument is large enough to give us, by comparison with this column, any idea of such a height. If the base of the column were situated at sea level, a person at the top could look down on the summit of Mount Washington, N. H., and it would overtop every mountain in this country east of the Rockies.

Our column of coal includes both anthracite and bituminous. In the last two years there has been a considerable falling off in the use of anthracite, while bituminous coal mixed with coke has shown a great increase over former years, so that our column would probably be made up of two parts bituminous to one part anthracite coal. Their combined bulk would form a column 200 feet square by 1,300 feet high - a midget in comparison to the coke column, but not so small after all when compared with the Park Row Building.

Charcoal, which is the smallest item in the fuel statistics for 1902, or about one-fifth of the number of tons of coal, yet forms a column nearly two-thirds the height of the coal column, or twice that of the Park Row Building.