Heating homes. We are so accustomed to living in heated homes that it is only when something goes wrong with the furnace that we give any thought to the blessed fire. To the savage shivering in his cave, however, a fire was a real blessing, even if it did fill his eyes with smoke. Keeping the home fires burning

　　was a difficult task for the American Indian, who delegated this to his wife. Woe be to the squaw who let the fire go out. In the wintertime, the fire was built on the ground in the center of the tent, which had a small hole in the top to act as a smokestack. Even the palaces of the wealthy in the Middle Ages were cold and damp, the fireplaces being so inefficient that only a portion of one room could be heated at a time. Not until a comparatively recent date were stoves invented, and furnaces were unknown even when your grandfather was a boy.

　　How fires are started and stopped. You have learned that burning is rapid oxidation which gives off light and heat. In order to start a fire, three conditions are necessary: something to burn; something to support the combustion; and a means of lighting the fuel . Having lived all his life in a home where the furnace is kept burning all winter, the average person seldom thinks of the difficulty of starting a fire.

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