576 MAN AS A CONQUEROR 



Although the advance of civilization has been coupled with the 

 domestication of animals, particularly as beasts of burden, many 

 other values might be noted. The furs of many wild animals, 

 especially the carnivores, such as seals, otters, sables, minks, and 

 others, are of much economic importance. Among the domesticated 

 animals, sheep. Angora and Cashmere goats, the camel, and alpaca 

 are most used. Nor can we omit the larva of the moth, Bombex 

 mori, which produces raw silk, the basis of an important industry 

 in China, Japan, Italy, and France. 



Many other economic values depend upon animals. In past ages 

 protozoans, as well as diatoms, had an important part in rock- 

 building and today their skeletons form the basis of some of our 

 polishing powders. Nor must we forget their place in the formation 

 of oil deposits, since the shells of diatoms and foraminifera in the 

 deep borings are almost always indicative of the presence of oil. 

 Corals have played a considerable part in the formation of islands 

 and the red coral of the Mediterranean is valued for ornamental 

 purposes. Pearls, the finest of which come from the north coast of 

 the island of Ceylon, are formed by the secretion of mother-of-pearl 

 by the mantle of the clam or oyster around some irritating substance, 

 such as a grain of sand or a parasite. The pearl button industry in 

 this country is largely dependent upon fresh-water mussels, shells of 

 which are cut into buttons. 



Whale oil, obtained from the ''blubber" of several species of whales, 

 and formerly used for illumination, has now become a commercial 

 lubricating oil. Neat's-foot oil, derived from the hoofs of cattle, is 

 another commercial lubricant. Tallow, from both cattle and sheep, 

 and lard from hogs have many well-known uses. Cod-liver oil, a 

 by-product of the codfish, is used for medical purposes. There is 

 obtained, too, from the menhaden of the Atlantic coast, an oil used in 

 dressing leather and making paints. Great quantities of menhaden 

 go into the manufacture of fertilizers. Leather made from the skins 

 of cattle, horses, sheep, goats, alligators, and snakes is put on the 

 market in the form of shoes, pocketbooks, coats, gloves, and other 

 articles. Horns and bones are utilized, for making glue as well as 

 combs, buttons, and handles for brushes. Ivory is obtained from 

 the tusks of the elephant, walrus, and other animals. The musk 

 deer, musk ox, and muskrat furnish musk used in the preparation of 

 certain perfumes. Ambergris, a basis for delicate perfumes, is formed 

 in the intestines of the sperm whale. 



