reless cookers, an invention of recent years, go far toward
solving the problem of waste by long hours of cooking single articles,
and each year we see more prepared food bought in order to save the
cost of heat. Housekeepers find that it does not pay to bake their bread
themselves, since a dozen loaves can be baked in a large oven with the
fuel used in baking one at home.

Briquettes are a new form of fuel made from coal, principally for
household use. They are made from the low-grade coals, culm, slack and
lignites, blended with coal-tar pitch. They are commonly used not only
in households, but for locomotives and ships, in several European
countries, especially Germany; but in this country the cost of making
them--about a dollar per ton--makes the retail price higher than the
cheaper grades of coal, and their general introduction at the price of
the higher grades is rather slow.

Let it always be kept in mind that we must not check the careful use,
only the waste, and the best way to avoid an unnecessary drain on the
coal and at the same time increase our manufactures is to substitute
other power. Coal is only a form of energy that came originally from the
sun. The same causes that produced coal still exist. Scientists tell us
that coal is still being made, but it will take thousands of years to
perfect it. If we could only learn to take the sun's heat directly and
use it for our heat, light, and power, it would be one of the greatest
discoveries in the history of the world, greater even than the discovery
of electricity.

Many attempts have been made to produce power directly from the sun
through solar engines, or by concentrating it in furnaces. At the St.
Louis Exposition a few years ago, a Portuguese priest exhibited a solar
engine called a heliophore, in which, by means of the sun's rays, the
temperature was raised to 6000 degrees F., and a cube of iron placed in
it melted like a snowball. The sun helps to raise the tides and some day
they may be used to produce power. Many experiments are being made with
both solar and tidal energy, some of them successful in a small way, but
nothing that is ready to stand the test of every-day use has been
devised.

Doctor Pritchell says that on a clear day when the sun is high, it
delivers upon each acre of the earth's surface exposed to its rays, the
equal of 7,500 horse-power working continually. If the extra energy not
needed for the growth of plants and animals could