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 fines, the closing of stores or bakeries, or by depriving the offender of his supply for a given length of time. Kitchens were established in large communities where housewives could learn the best ways of making bread with the use of various substitutes for wheat.