354.HOW WERE LAMPS FIRST MADE?
Before man discovered fire, the only heat and light he had was provided by the sun. Since he couldn’t control this, he was quite helpless in dealing with cold and darkness.
Probably more than 100,000 years ago, he discovered fire. Then he began to notice that some materials burned better than others. Perhaps he observed that fat dripping into the fire from roasting meat burned brightly. As time passed, man began to select materials which, when burned, provided better light.
353.HOW IS ROPE MADE?
Men have always needed rope for the rigging of ships, for hauling things, and for tying bundles. So rope-making is one of the oldest industries in existence. The first ropes were knotted together from leather thongs, pieces of bark, or even roots. The ancient Egyptians made ropes from vegetable fibers, and these resemble the ropes made today.
352.HOW DOES A WINDMILL WORK?
No one knows where or by whom the windmill was invented. A boat can sail at right angles to the wind by slanting its sail slightly. In the same way, the “fan” or “sail” of a windmill can be driven around in a circle even when placed at right angles to the wind. The windmill is like a huge propeller, with the source of power that turns it coming from the wind instead of a machine.
