208 THE TROUT 



the water show a tendency to become heated, the 

 supply must be increased or you will run a serious 

 risk of loss. 



To have complete control over the supply, and 

 to be able to create an artificial 'spate' by sending 

 down a flush of additional brook-water into your 

 ponds whenever you think it desirable, is a very great 

 advantage. 



The use of a Hornsby-Akroyd oil pumping-engine 

 at the Weston Fishery, for the purpose of increasing 

 at will the natural supply of brook-water during the 

 hottest days of the summer, has been attended with 

 great success. 



In respect to size, your ponds should be small for 

 rearing purposes. ' When you mean business,' says 

 Livingston Stone, ' build your ponds small ; never 

 let a trout escape to any place where you cannot get 

 at it, observe it, and capture it at a moment's notice.' 



The shape of your rearing-ponds will depend upon 

 circumstances ; generally it is convenient to have them 

 oblong. If the water supply is not very plentiful or 

 cool the ponds should be deep and narrow, exposing a 

 smaller surface to the rays of the sun. 



The quantity of water entering your ponds may be 

 regulated by a hatch at the intake. In front of this 

 is a sloping screen of perforated zinc designed to 



