Milk
a whitish fluid secreted by mammals for the nourishment of the young. The two milk glands of the elephant are situated between the fore legs; those of the mare between the hind legs; those of the sow, the cat, and the mouse are distributed in two rows along the entire abdomen. Most domestic animals have two glands or teats. The cow has four.
The milk of the cow, reindeer, mare, ass, yak, buffalo, goat, ewe, and camel are used for food. Milk contains minute globules of fat suspended in a solution--albumin, milk-sugar, casein, and salts. Human milk contains about 87.4 per cent of water, 3.4 per cent fat, 1.2 per cent albumin, 7 per cent sugar, and one-fifth of one per cent ash. It is slightly alkaline. Cow's milk contains a trifle less fat and more sugar; ewe's milk is the richest of all. Mare's milk is the poorest. Named in order of fat or butter content, the milk from dairy cows ranks about as follows: Jersey, 5.19; Guernsey, 5.16; Shorthorn, 4.05; Ayrshire, 3.64; Holstein, 3.43. The flow of milk may be increased by judicious feeding but the richness of the milk from a particular cow is not subject to much variation.
Of late milk has begun to play a large part in the arts. Inventive Austrian manufacturers have discovered that the casein of skimmed milk may be mixed with formalin and converted into a horn-like substance which makes an excellent substitute for celluloid, bone, horn, rubber, and amber. The finest, whitest quality makes a substitute for ivory. It is used for piano keys. It is smooth to the touch and is proof against soap and water. It does not crack or chip, and is capable of being turned and carved like ivory. Galalith or milk stone, as this artificial substance is called, supplies an excellent material for billiard balls, handles, toilet boxes, penholders, dolls' heads, knife handles, door knobs, clocks, pin heads, collar buttons, picture frames, and a host of other articles for which an ivory or celluloid effect is desired. The factories of Austria convert 100,000 quarts of skimmed milk a day into galalith.