MAINE AGRICULTURAL EXPERIMENT STATION. 87 



rat destroyers, which when fed to rats is supposed to induce a 

 disease which kills them all. No effect whatever was observed 

 to follow the use of this preparation. The rats ate freely of 

 grain which had been moistened with it and if any disease 

 developed as a consequence it has not yet benefited us, or per- 

 ceptibly inconvenienced the rats. Digging the rats out of their 

 holes and shooting them is one effectual method of dealing 

 with them. Several good cats on the place also aid materially in 

 fighting this pest. A systematic trapping campaign is productive 

 of good results. It must however, be continued without inter- 

 ruption over a considerable period of time. Desultory trapping 

 produces little effect on the rat population. A thorough-going 

 campaign, however, tends to drive the uncaught rats away from 

 the premises. 



TRAP NESTS. 



In all the experimental work with laying hens at the Maine 

 Agricultural Experiment Station use is made of trap nests. In 

 1908 a new type of trap nest was devised which has proved 

 extremely satisfactory. The features in which this nest is 

 superior to the type formerly used at the Station are (i) cer- 

 tainty and precision of operation; (2) greater simplicity of con- 

 struction, with less tendency to get out of order and work 

 badly; (3) saving of labor in resetting the nest after use. 



The nest is a box-like structure, without front, end, or cover, 

 28 inches long, 13 inches wide, and 16 inches deep, inside meas- 

 ure. A division board with a circular opening 71-2 inches in 

 diameter is placed across the box 12 inches from the rear end 

 and 15 inches from the front end. Instead of having the par- 

 tition between the two parts of the nest made with a circular 

 hole, it is possible to have simply a straight board partition 

 extending up 6 inches from the bottom, as shown in figure 23. 

 The rear section is the nest proper. 



The front portion of the nest has no fixed tottom. Instead 

 there is a movable bottom or treadle which is hinged at the back 

 end (fig. 23). To this treadle is hinged the door of the nest. 

 The treadle is made of i-2-inch pine stuff, with I T-2-inc)i hard- 

 wood cleats at each end (figs. 24 and 25) to hold the screws 

 which fasten the hinges. It is 12 inches wide and 12 1-4 inches 



