hat had been making powder, guns, shells,
and other munitions for the Allies started to make these things for the
United States. This was easy to arrange, since England and France had
about reached a position where they were able to supply themselves.
Besides, great quantities of food and clothing were also needed, and the
meat packers and the manufacturers of textiles, shoes, and other
articles turned their plants to the production of supplies for the army.

AIRCRAFT.--The war in Europe had shown the high usefulness of aircraft
as part of the military forces. Recognizing this, Congress appropriated
two thirds of a billion dollars for the purpose of constructing
thousands of airplanes and for training thousands of pilots and other
experts to use them. Unfortunately much time was lost in building
manufacturing plants and in experimenting with various types of engines
and other parts of airplanes. Only a small part of the twenty thousand
it had been planned to send to France by June, 1918, were completed at
that time. Meanwhile, however, engineers had developed, on the basis of
the automobile engine, an improved engine known as the Liberty Motor,
and the production of efficient airplanes was at last going ahead
rapidly.

_Food and Fuel Control._--So large a proportion of the population of the
European countries is employed in carrying on the war that there has
been a constant decrease in the amount of food produced in Europe.
Fortunately, up to 1917 this country had enough for itself and
sufficient to spare for the Allies and the neutral nations. In 1917
there was an unusually short cereal crop all over the world. The result
was that there was not enough food to go round, if every one in this
country ate as much as usual.

In order that proper conservation of food might be brought about, a food
commission was created, not only to prevent profiteering, but also to
direct how the people should economize in order to help win the war.
Shortages in various kinds of food were controlled at first through
voluntary rationing under requests made by the Food Administrator. Later
on, limits were placed on the amount of wheat, flour, and sugar that
could be bought by large dealers and bakeries. A certain proportion of
other cereals had to be purchased with each purchase of wheat. Bakers
were required to make their bread with a proportion of other flours
mixed with the wheat. These regulations were enforced by such
punishments as f