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When the nest is open the door extends horizontally in front, as 

 shown in figure 2. In this position, the side strips of the door rest 

 on a strip of beech one and one-half inches wide, beveled on the inner 

 corner, which extends across the front of the nest. This beech strip 

 is nailed to the top of a board four inches wide, which forms the 

 front of the nest box proper. To the bottom of this is nailed a strip 

 two inches wide, into which are set two four-inch spikes from which 

 the heads have been cut. (Compare Fig. 2.) The treadle rests on 



Trap nest closed. One side removed to show method of operet ion. 

 Fig. 3. 



these spikes when the nest is closed. The hinges used in fastening the 

 treadle and door are narrow three-inch galvanized butts with brass 

 pins, made to work very easily. It is necessary to use hinges which 

 will not rust. 



The manner in which the nest operates will be clear from an ex- 

 amination of figures 1 and 2, which show a sample nest with one 

 side removed to show the inside. A hen about to lay steps up on the 

 door and walks in toward the dark back of the nest. When she 

 passes the point where the door is hinged to the treadle her weight 

 on the treadle causes it to drop. This at the same pulls the door up 

 behind her, as shown in figure 3. It is then impossible for the hen 

 to get out of the nest till the attendant lifts door and treadle and 

 resets it. It will be seen that the nest is extremely simple. It has no- 

 locks or triggers to get out of order. Yet, by proper balancing of 

 door and treadle it can be so delicately adjusted that a weight of less 

 than half a pound on the treadle will spring the trap. All bearing 

 surfaces are made of beech because of the well-known property of 

 this wood to take on a highly polished surface with wear. The nests 

 in use at the Maine station have the doors of hard wood, in order to 

 get greater durability. Where trap nests are constantly in use, flimsy 

 construction is not economical in the long run. For temporary use 

 the nest door could be constructed of soft wood. 



The trap nests are not made with covers because they are used 

 in tiers and slide in and out like drawers. They can be carried away 

 for cleaning when necessary. Four nests in a pen accommodate 

 twenty hens by the attendant going through the pens once an hour, 

 or a little oftener, during that part of the day when the hens are 

 busiest. Earlier and later in the day his visits are not so frequent. 

 The hens must all have leg bands in order to identify them ; a num- 

 ber of different kinds are on the market. The double box with the 

 nest in the rear is necessary. When a hen has laid an egg and desires 

 to leave the nest, she steps out into the front space and remains 

 there until she is released. With only one section she would be likely 



