Page:Popular Science Monthly Volume 38.djvu/481

 at what rate the technology of the manufacture of anthracite iron has advanced during these years, we will compare the product of the furnace of 1840 with that of the furnaces on the same ground at the present time. The original furnace made in the year ending July 1. 1841, 2,460 tons; and the present plant (five furnaces) produced during the year ending July 1, 1890, 111,828 tons, or at the rate of 22,365 tons per furnace (on the supposition that they were all running), which is more than nine times the product of the furnace built in 1840 at that place.

The production of pig iron in the United States for the year ending June 30, 1890, was the largest in the history of the country, and, in fact, larger than that of any other nation in the world, being 258,216 tons in excess of the production of Great Britain in 1889. The following table exhibits the rate of increase of production of pig iron during the past twenty years:

From the above figures we see that the manufacture of pig iron in New England has been practically stationary for the past twenty years, while in the Middle States it has nearly quadrupled, in the Western States it has increased nearly five times, and in the Southern States nearly ten times in the same period.

Few persons save those connected with the manufacture of pig iron are aware of the enormous and insatiable appetite of one of the largest blast-furnaces; and the figures hitherto given fail to convey an adequate idea of the immense quantity of materials that pass through such a furnace, and it is only when the total daily amount of these materials is considered that the tremendous igneous activities constantly at work in that combination of hurricane and volcano—a modern blast-furnace of the first class—