58 



The Illustrated Book of Poultry. 



lettered as in the preceding figures, but it will be seen that the flue F branches, discharging the hot 

 water at the end of the tank. Striking there the current is reflected", and passes round the outside 

 of the tank, as it cools being drawn towards the centre, from whence it passes by the flue R to the 

 boiler again. The object of this construction is to obviate a great fault in nearly all other 



incubators, of the outer edges of the egg-drawer being much cooler than the inside ; by this 

 arrangement the middle of the tank is the coolest, and the heat is much more equalised. V V are 

 tubes two and a half inches in diameter, passing through the tank, and open at both ends. The 

 joints.where they pass through the tank must be made perfectly tight, the object being to ventilate 

 the egg-drawer, and also to let off the heated air when required into the top part of the machine, 

 which serves as a chickcn-nurserj^ If the apparatus be designed for a warm room, the tubes may 

 go higher, so as to open into the outside air instead of into the nursery. They are also seen similarly 

 lettered in Fig. 35, and are provided at the top with swing or pivot valves, the rod on which these 

 turn being carried through the end of the macliine and terminating with a lever as shown at A 

 (Fig- 35). which is connected with the regulator by a rod, X. The tank is supported in its position 

 two inches above the egg-drawer by a few battens or slips fastened to the outer case. 



Fig. 39- 



Fig. 40. 



Fig. 39 represents the drawer or nest. This is in three parts : first the wooden box, the bottom 

 of which is of slats or strips one and a half inches wide and three to five inches apart; next a 

 galvanised iron or zinc pan, fitting snugly inside the box; and, lastly, a tray, fitting loosely inside the 

 pan. This tray is constructed of strips of the same material of which the pan is made, bent like 

 an inverted V and placed thus AAAA ; these arc placed upon three tubes or strips of the same, 

 crossing at right angles and all soldered fast to them. The whole is then embraced within a band 

 about two inches wide, furnished with handles at each end so that the tray can be lifted out. 

 When using, a woollen blanket or cloth is laid on the strips, dropping down between each or every 

 alternate strip, into or just touching the water with which the pan is filled to the depth of a quarter 

 of an inch. This construction provides moisture, and also keeps the bottom of the eggs cool ; the 

 pan coming in direct contact with the outer air between the slats forming the bottom of the 

 drawer. In this manner we get as n_early as possible the same effect as when a hen forms her nest 

 on the damp ground, in which case she is almost certain to hatch nine-tenths of her eggs. On this 

 blanket the eggs arc laid, the A strips keeping them in rows and preventing them from rolling 

 about ; hence the strips should be placed about one and tlirce-quartcr inches apart, measuring 

 from centres, in order that the eggs may lie snugly between. In the front of the drawer is a small 



