The Boston cooking-school cook book

and abundant, constantly bearing in mind that this is a period of great mental and physical growth. Where children have broken down, supposedly from over-work, the cause has often been traced to impoverished diet. It must not be forgotten that digestive processes go on so rapidly that the stomach is soon emptied. Thanks to the institutor of the school luncheon-counter! The daily average ration of an adult requires 4½ oz. proteid 2 oz. fat 18 oz. starch 5 pints water About one-third of the water is taken in our food, the remainder as a beverage. To keep in health and do the best mental and physical work, authorities agree that a mixed diet is suited for temperate climates, although sound arguments appear from the vegetarian. Women, even though they do the same amount of work as men, as a rule require less food. Brain workers should take their proteid in a form easily digested. In consideration of this fact, fish and eggs form desirable substitutes for meat. The working man needs quantity as well as quality, that the stomach may have something to act upon. Corned beef, cabbage, brown-bread, and pastry, will not overtax his digestion. In old age the digestive organs lessen in activity, and the diet should be almost as simple as that of a child, increasing the amount of carbohydrates and decreasing the amount of proteids and fat. Many diseases which occur after middle life are due to eating and drinking such foods as were indulged in during vigorous manhood. WATER (H_{2}O) Water is a transparent, odorless, tasteless liquid. It is derived from five sources,—rains, rivers, surface-water or shallow wells, deep wells, and springs. Water is never found pure in nature; it is nearly pure when gathered in an open field, after a heavy rainfall, or from springs. For town and city supply, surface-water is furnished by some adjacent pond or lake. Samples of such water are carefully and frequently analyzed, to make sure that it is not polluted with disease germs. The hardness of water depends upon the amount of salts of lime and magnesia which