Although it is true, as already stated, that Germany normally produces about 80 percent. of her food needs, making it seem possible for the nation to meet the blockade emergency by repressing consumption by 10 per cent. and increasing production by 10 per cent. this does not mean that they normally produce 80 per cent. of each kind of food consumed by them. As a matter of fact, they produce more than their total needs of certain kinds of food, as sugar, for example, and less than 80 per cent. of certain other kinds. And while there is a possibility of substituting, within certain limits, one kind of food for another, so that a shortage of wheat might be made up by an abundance of rye, or a shortage of bread-grains in general be made up, in some degree, by increasing the ration of potatoes, if they are available, this substitution cannot go to the extent of substituting pure carbo-hydrate or starchy foods like potatoes, which simply produce heat or energy for the body, for the protein foods like meat, fish, eggs and dairy products which produce not only energy but new tissues. A child must have protein food in order to grow; an adult must have it in order to replace the tissues worn out by daily work. Also, there are certain peculiar and so far little understood elements, called vitamines, found only in certain kinds of food, notably fats, milk and the green vegetables, which are essential to the proper metabolism of the body. [Illustration: Photo by P. Thompson The Battle Scene at Home During the war the Allies called on the United States for food in far greater quantities than we had ever dreamed of exporting. For example, in the last years before the war we had been sending yearly to Europe about five million tons of food. In 1918 alone we shipped more than fourteen million tons of foodstuffs overseas.] GERMANY'S FOOD PROBLEM Now in the light of these needs for proper feeding, and in the light of the special conditions produced by the war, what was Germany's food problem through the war? It was that of attempting to increase production when the men and work animals had been sent to the fighting lines, of repressing consumption when both men in the army and the men in the war factories had to be well fed in order to fight well and work well, of attempting to get in food from outside the country when a blockade was steadily closing the borders ever and ever more tightly, and finally, of trying to get the people to modify their food habits in the way of accepting substitutes and using strange new semi-artificial foods in place of the familiar staples.