that we may get some idea of how much energy is furnished in our common foods a table is given below. The figures are for the numbers of calories in a pound of the food material as purchased in the market. In most vegetables and meats there is a loss of about ten per cent in preparing them for the table, or, in the case of meat, in the bones. The figures were prepared by officials of the United States Government in arranging dietaries for the Army. CALORIES PER POUND AS PURCHASED Apples, fresh 219 Bacon 2,979 Bananas 298 Beans, dried 1,603 Beef, fresh 1,009 Bread 1,300 Butter 3,478 Cabbage 124 Celery 70 Cheese, American 1,948 Chocolate 2,858 Eggs 614 Fish, salmon, canned 679 Fish, fresh 368 Flour 1,651 Lard and substitutes 4,218 Milk 302 Pork, salt 2,948 Potatoes, white 311 Rice 1,631 Sugar 1,860 Tomatoes 106 Very few of our foodstuffs are exclusively of one kind of material; that is they are not exclusively protein or exclusively fat or exclusively of sugar or starch compounds. Most vegetables are mixtures of starch with protein, fruits are mixtures of starch and sugar with a little protein, both fruits and vegetables contain so much water that their actual fuel value per pound amounts to little. Meats are mixtures of proteins with fats. Milk is a mixture of proteins, sugar, and fat. Table sugar and butter are as near pure unmixed foodstuffs as any of the things we commonly eat. In an earlier part of the chapter we saw that about two-thirds of our ordinary diet is of starch or starchlike materials. This figure is given, not in weight of material, but in the energy value. What it means is that about two-thirds of the energy for our metabolism comes from the starch and sugar that we eat; the other one-third is divided between fat and protein in the proportion of about two to one. The energy we get from fat being about double that which we get from protein--since a given weight of fat has about twice the energy value of the same weight of protein--we actually eat about the same amount of protein as of fat. The combined weight of the starch and sugar is between four and five times that of the protein. These, of course, are average figures representing not what we eat at any one meal, but the way in which the foodstuffs are found to be divided in our diet taken as a whole. Where meals have to be planned on a large scale, as in armies or in institutions where the persons to eat the food have not much choice in selecting them, it is necessary that the diets be arranged both to give the proper amounts of material and also to furnish them in about the correct proportions.