“Blew bellows, didn’t he?” queried Mr. Prescott.
“Sure,” answered Billy. “Sometimes he used to let me do that.”
“Well, then,” said Mr. Prescott, “just remember three things: fuel, blast, and hammer—power, of course, behind the hammer. It’s the different variations that men have been making on those three things that have brought iron where it is to-day.
“Iron ore has so many things besides iron in it that the problem has always been how to get the impurities out.
“The old blacksmiths used to put it in the fire and hammer it; put it back in the fire and hammer again, until they worked most of the other things out. They made what is called forge iron.
“Then an Englishman, named Cort, found a way to burn and roll the impurities out. The thing they particularly wanted to get rid of was carbon, because that makes iron too brittle to use for a great many things.
“They worked away till a man—Sir Henry Bessemer—found a way to burn out all the carbon, and to make a kind of steel called Bessemer steel.
“Steel is, technically, an alloy of iron and carbon. The point is to have the carbon added to the iron in just the right proportion to make the kind of steel that you may happen to want.
“Bessemer—he was an Englishman, too—invented a converter to put carbon back into iron, that is, to make iron into steel.
“When it comes to telling you about steels, I can’t do that to-day; there are too many kinds.