156 EQUIPPING THE POULTRY HOUSE 
dishes. Metal pails and pans, although relatively cheap and easy 
to fill and empty, are not as efficient as a well-built vacuum 
fountain. 
The “vacuum” fountain consists of a large chamber filled 
with water having only one outlet, which is in the lower part of 
the chamber, communicating directly with a shallow pan or trough, 
the edges of which are above the opening in the water chamber. 
When the vessel is filled and set 
To ~ upright, and the water has filled 
-“ the saucer or cup, air is prevented 
from entering the water chamber, 
and a closed chamber called a 
“vacuum ” is formed on the top. 
Outside air pressure holds the 
water in. 
From among the various com- 
mercial types of drinking vessels 
which are found on the market a 
number of practical ones can be 
selected. In selecting a commer- 
cial drinking fountain it is very 
desirable to secure onewhich allows 
of separating the water chamber 
from the drinking pan, as more 
easily and perfectly cleaned and 
more easily filled. These commer- 
cial drinking fountains can be 
secured in all sizes from that re- 
Fie. 104.—A hopper for gritand shell. Quired for baby chicks to those for 
These materials are usually fed separately 
—not with dry mash. adult flocks. 
The usual commercial fountains 
‘are not large enough for a large number of hens and they 
are rather expensive. Figure 103 shows a practical device which 
answers all the requirements outlined. 
Grit and Shell Boxes.—The most economical way to feed grit 
and shell is to keep it before the birds all the time. There are 
hoppers constructed for that purpose (Fig. 104). In this way the 
birds can have constant access to this material, and the cost of 
feeding it is reduced to a minimum. These hoppers resemble in 
style a large dry-mash hopper, but are usually much smaller. A 
very common practice, and a very good one, is to partition off 
