The Sources of Animal Products 
01 
faster our population grows the more necessary it becomes that the 
people of Europe and America, like those of the Orient, learn to use 
more of such foods as beans, fish, and milk. For a given amount of 
food. milk needs much less farm land than beef. 
SHEEP AND WOOL 
Sheep are, if anything, more generous to man than cattle or swine. 
They yield not only meat that is highly prized and leather that is 
especially useful for shoes and bookbindings, but wool that is con- 
verted into clothing, hats, and blankets. Moreover, sheep can thrive 
in a great variety of climates. It is not surprising, therefore, that 
sheep are raised throughout the inhabited world wherever grass can 
be found, or that they are the most numerous domestic animals, 
aside from hens. 
Sheep in the tropics. Within the tropics, however, the warmth 
makes sheep become hairy, like goats, instead of woolly, and the poor 
and limited supply of grass makes them lean and lanky. There the 
skin is the most valuable part of a sheep, and it is not worth while to 
raise them for the sake of exporting this one product. 
In the temperate zones. In the temperate zones sheep are covered 
with wool of good quality and are fat enough to yield large quantities 
of mutton. But the same sheep rarely produces both fine wool and 
UNITED ST 
SHEEP AND LAME 
(ON FARMS AND RANT" 
NUMBER JAN. {, 
EACH DOT REPRESEN 
5 000 HEAD 
Fig. 70. In the West, sheep are raised chiefly in the Rocky Mountain states and on semi-arid 
lands. In the East, the industry tends to be concentrated in the hilly pasture sections of Ohio 
and southern Michigan.