ARTIFICIAL INCUBATION. 69 
moist s nd 1nder the egg-drawer, and by a few wet 
sponges :n the egg-drawer. 
These incubatois do not require any watching. No 
one gets up inthe night to look after them. The large 
body of sawdust absorbs heat, and gives it up to the 
egg-drawer as it begins to cool; hence, the heat varies 
very slowly. Ifa lamp is preferred, it may be attached 
by having two tubes, one above the other, extending to 
a small ‘‘boiler” outside, which is heated by a lamp, 
capable of accurate regulation, in the usual way. 
HOW TO MAKE AN INCUBATOR. 
To make this incubator, get your tinner to make you 
atank fifteen inches wide, thirty inches long, and 
twelve inches deep, of galvanized iron or zinc, the iron 
being preferable. On the top should be a tube one inch 
in diameter and eight inches high. In front should be 
another tube, nine inches long, to which should be at- 
tached a spigot. 
Having made your tank, have what is called the ven- 
tilator made, which is a wooden box with a bottom, but 
notop. The ventilator should be eight inches deep, and 
one inch smaller all around than the tank, as the tank 
must rest on inch boards, placed upright to support it, 
or on iron rods. In the ventilator should be two or 
three tin tubes, one half inch in diameter and six inches 
long. ‘They should extend through the bottom, so as to 
admit air from below, and to within two inches of the 
top, or a little less. 
Now make an egg-drawer, which is a frame of wood, 
three inches deep, having no top or bottom, except at 
the front, where it is boxed off and filled with sawdust, 
which is covered over afterward with a piece of muslin, 
