SWIXE RAISING IX HAWAII. 
11 
rated with crude oil, on posts at a height which will permit of the> 
animals rubbing against them. The sacks should be frequently 
saturated with the oil. 
Hog wallows. — A good hog wallow should be accessible to the swine. 
Fig. 11. — Concrete wallow. Crude oil on water surface to destroy vermin. 
It not only affords a cool, refreshing bath in hot weather but it also 
is- very effective in freeing the animals from flies and scurf. Wallows 
of concrete construction are more sanitary than mud wallows. The 
addition of sufficient crude oil to form a thin film over the surface 
of the water tends to keep 
the animals free from 
skin parasites. (Figs. 10 
and 11.) 
Self-feeders and pig 
creeps. — No hog farm is 
complete without the self- 
feeder. (Figs. 12 and 
13.) This device enables 
the hogs to satisfy their 
craving for feed at any 
time, and is perhaps the 
most economical method of 
fattening the animals, be- 
cause, while a slightly 
increased amount of grain may be consumed, it requires the least 
labor. The self-feeder should be made of well tongued and grooved 
boards having a planed surface. The smoother and straighter the 
sides the more readily will the feed flow. The feeder should be pro- 
vided with a good rain-proof cover to prevent the feed from getting 
wet and spoiling when in use out of doors, and the size of the open- 
Fig. 12. — Large self-feeder for whole algaroba beans. 
