The gas-light proved to be so much better than even the best of lamps, that in towns and cities almost everybody who could afford to do so laid aside the old wick-lamp and burned gas. About 1876, however, a new kind of light began to appear. This was the electric light. The powerful arc light (Fig. 9), made by the passage of a current of electricity between two carbon points, was the first to be invented. This gave as much light as a hundred gas-jets or several hundred lamps. Such a light was excellent for lighting streets, but its painful glare and its sputtering rendered it unfit for use within doors. It was not long, however, before an electric light was invented which could be used anywhere. This was the famous Edison's incandescent or glow lamp (Fig. 10), which we see on every hand. Edison's invention is only a few years old, yet there are already more than thirty million incandescent lamps in use in the United States alone.
FIG. 10.—AN INCANDESCENT ELECTRIC LIGHT.
The torch, the candle, the lamp, the gas-light, the electric light,—these are the steps of the development of the lamp. And how marvelous a growth it is! How great the triumph over darkness! In the beginning a piece of wood burns with a dull flame, and fills the dingy wigwam or cave with soot and smoke; now, at the pressure of a button, the house is filled with a light that rivals the light of day, with not a particle of smoke or soot or harmful gas. Are there to be further triumphs in the art of lighting? Are we to have a light that shall drive out the electric light? Only time can tell.
[THE FORGE]
After men had learned how to use fire for cooking and heating and lighting they slowly learned how to use it when working with metals. In the earliest times metals were not used. For long ages stone was the only material that man could fashion and shape to his use. During this period, sometimes called the "stone age," weapons were made of stone; dishes and cooking utensils were made of stone; and even the poor, rude tools of the age were made of stone (Fig. 1).
