584 



General Notices: 



The same letters refer 

 to each of the figures. 



a, End view of the trap, 

 with the tub (sec- 

 tion). 



b, Longitudinal section 

 of trap. 



c, Birdseye view of 

 longitudinal section 

 of trap. 



a, Doubting Castle. 



b, Forlorn Hope. 



c, Slough of Despond. 



d, Partition wall. 



e, Ground level. 



/, Pipe of brick or tile. 



g, Falling floor, or bot- 

 tom of trap. 



h, The weighted end 

 of the fall, to bring 

 it back into its place. 



i, The end of the fall, 

 that gives way under 

 the rats. 



/, Trough, or thorough- 

 fare, in which the 

 trap (rt) is placed. 



m, The feeding end of 

 the trough. 



n, The end at which 

 the rats enter. 



o, Loose ' wood, to 

 serve both as a cover 

 and a road into the 

 trap. 



p, A slip of wood, to 

 which the rats spring 

 from the pipe/, and 

 which gives way un- 

 der them, and lets 

 them into the water 

 below. 



trap will be no trap to them ; and yet the catch or fastening should not be 

 so stiff but that it will suffer the bridge to give way under then* weight 

 when once upon it. I cannot show this catch in my sketches; they are so 

 small, but (enlarging the scale) it is, when the bridge is viewed sideways, 

 something like the following sketch. (Jig. 112.) g is the bridge or fall of 

 wood tipped with thin sheet iron at the end (i), which works into the 

 catch (?•). This catch should be sufficiently rank to bear the trial already 



