From Cooking Wiki
Water
Water forms more than two thirds of the whole body. It is especially abundant in the blood and secretions. It gives them the necessary fluidity, and enables them to dissolve the important materials they contain. It is contained in all kinds of solid food, as well as in the liquids drunk as beverages. It is most abundant in fruits and vegetables. Every pound of perfectly dry food should be accompanied with four pounds of water.
Pure water is composed of oxygen and hydrogen, one ninth hydrogen and eight ninths oxygen by weight. The usual test for pure drinking water is that it be " free from color, smell, or taste, be soft, bright, and aerated, and free from all deposit."
But it is very seldom found in that condition, as its power of dissolving other substances is so great that it nearly always holds animal, vegetable, or mineral matters in solution, obtained from the earth through which it flows. It also absorbs gases and odors from the air. The animal and vegetable substances found in it render it impure. But the mineral matters, unless in excess, are not objectionable.
When water contains more than a few grains to the gallon of carbonate of lime, it is termed hard water. When water is hard or impure, it should be boiled before being used for drinking, as this destroys the vegetable and animal impurities.
Water evaporates at all temperatures, boils at 212, and freezes at 32 Fahrenheit. In freezing, the substances dissolved in water are expelled. Water, as it approaches the freezing-point, expands, and often bursts the vessels in which it is contained.
In ponds or rivers it expands, becomes lighter, freezes, and floats on the surface in the form of ice.
Water is perfectly neutral. It combines with acids and with bases. It becomes sweet, sour, salt, astringent, bitter, or poison ous, according to the nature of the bodies it holds in solution.
