The great advantage of electricity is that little heat is lost in radiation, and that the degree of heat is well under control. There are also no products of combustion present, and this is the only source of heat for cooking of which this is true. Both gas and kerosene vitiate the air to some extent.

Cooking apparatus.—The wastefulness of cooking operations, past and present, is due largely to the defects of the apparatus used. The open fireplace for wood, and the open grate for coal, are two arrangements that permit most of the heat to pass up the chimney, and into the room. See Frontispiece and Fig. 14. In Fig. 14 there is illustrated at the right a brick oven with a flue opening into the chimney. This was one of the earliest inventions for saving fuel and heat. This oven was lined with brick or stone, and the fire of wood was built in it, and allowed to remain until it had

burned out. The coals and ashes were removed, and when the brick had cooled somewhat cakes and pies were put in to bake. This oven retained its heat for twenty-four hours, and beans put in Saturday afternoon were taken out hot for the Sunday morning breakfast. The method was clumsy, but a good heat saver.

Fig. 14.—A colonial fireplace. Courtesy of the Historical Society, Ipswich, Mass.

Figure 15 is an American stove, early nineteenth century, wood the fuel; and from this form, modified for using coal, has developed the modern American coal range (Fig. 18). Even the latest types are very wasteful of heat. Stoves like that shown in Fig. 19 have been devised for use with gas. Even with these only a small percentage of the heat generated is available for cooking.

Fig. 15.—An early American stove, 1823. Courtesy of the Bryson Library.

The ideal system is that which gives the largest possible percentage of its heat for cooking, and puts the degree of

heat under quick control with the greatest saving of fuel, and of labor in operating. This does not mean that the stove which gives the most intense heat is the best, although some stoves seem to be constructed with that as the aim.