CRAIGEND. 



141 



The dam was only used for mature trout, and half-inch wire- 

 netting is sufficient to confine them. If the screen is deep enough 



FIG. 95 scale fa. 



in the water, ice and leaves do not interfere with its working. 

 All outlets of ponds in wild situations should be guarded on this 

 principle. If a smaller size of opening is required to confine the 

 fish, as in the case of yearlings or two-year-olds, it should be placed 

 6 inches in rear of the half-inch wire-netting ; the latter keeps 

 all leaves, etc., off the finer screen. Often a large mass collects 

 on the wire at least a foot in depth ; the screen, therefore, should 



Fro. 96 scale & 



