But ironmakers were soon to become busier than ever before. About the middle of the nineteenth century Sir Henry Bessemer invented a new process of making steel. Steel is only iron mixed with a small amount of carbon. Ironmakers have known how to make steel—and good steel, too—for thousands of years, but before the days of Bessemer the process had always been slow and tedious, and the cost of steel had always been very great. Bessemer undertook to make steel in large quantities and at low prices. In his experiments amid showers of molten metal he often risked his life, but his perseverance and courage were rewarded. By 1858 he had invented a process by which tons of molten iron could be run into a furnace and in a few minutes be converted into a fine quality of steel. This invention of Bessemer was the last great step in the history of the forge.
From copyright stereograph by Underwood & Underwood, N. Y.
Now that steel could be made in great quantities and at a low cost it was put to uses never dreamed of in former times. Soon the railroad rail was made of steel (Fig. 10), bridges were made of steel, ships of war were plated with steel. Then ocean grayhounds and battleships were made of steel, still later steel freight cars and steel passenger coaches were introduced, while in our own time we see vast quantities of steel used in the building of houses. So while the invention of Bessemer marked the last step in the history of the forge it also marked the ending of the Age of Iron and the beginning of the wonderful age in which we live—the Age of Steel.
[THE STEAM-ENGINE]
We have now traced the steps by which man mastered the art of kindling a fire quickly and easily and have followed the progress that has been made in the most common uses of fire. But the story of a most important use of fire remains to be told, the story of its use in doing man's work. How important this use is, how much of the world's work is done through the agency of fire, a little reflection will make plain. Fire makes steam and what does steam do? Its services are so many you could hardly name all of them. The great and many services of steam are made possible by the fire-engine, or steam-engine, and the story of this wonderful invention will now be told.
FIG. 1.—FIRST EXPERIMENTS WITH STEAM.