THE PIG AND HIS PRODUCTS 269 
growth is not possible, nor can the best thrift be ex- 
pected. The dipping tank offers an easy method of 
treatment. This may be made of concrete, or purchased 
ready made of galvanized iron. A homemade device 
for use except during winter is a shallow vat about 10 
inches deep and 10 to 12 feet square. It may be built of 
concrete or timber. It should be placed conveniently to 
the well or other watering place. The vat is partially 
filled with water and a quart of one of the coal tar dips 
added. The hogs will do their own dipping. The dip 
DoinGc THEIR Own DIPPING 
Home-made wallows like this may be constructed of boards or cement. If small 
quantities of disinfectants are added from time to time there will be no trouble 
from lice or skin diseases. 
is renewed once or twice a month and the water sup- 
plied as needed. No harm will result if the hogs drink 
some of the liquid. Occasionally, the mud, as it settles at 
the bottom of the vat, should be removed. 
14. Hogs are single-purpose animals.—Cattle furnish 
meat, milk, hides for clothing and sometimes labor. 
Sheep furnish meat, wool, hides and sometimes milk. 
Hogs, however, furnish only meat, lard and bristles. 
Hogs are, therefore, a single-purpose animal. The rea- 
son they can compete with other domestic animals is due 
to their prolificacy, to their ability to convert efficiently 
