He showed that the world's production of pig iron has increased in
round numbers from 10,500,000 tons in 1869 to 20,500,000 tons in 1882.
The blast furnaces of 1869 produced on the average a little over 180
tons per week, with a temperature of blast scarcely exceeding 800°
Fahr. The consumption of coke per ton of iron varied from 25 to 30
cwt. To-day our blast furnaces produce on the average upward of 300
tons per week.
The Consett Company have reached a production of 3,400 tons in four
weeks, or 850 tons per week, and of 134 tons in one day from a single
furnace.
From the United States we have authentic accounts of an average
production of 1,120 tons per furnace per week having been attained,
and that even this great output has lately been considerably exceeded
there. Both as to consumption of fuel and wear and tear, per ton of
iron produced, these enormous outputs are attended with economy.