36 



artificial pond where large numbers of Trout are kept, 

 and they tend to foul the water by hiding dead fish apd 

 bits of meat. It is best, it possible, to have ponds so ar- 

 ranged that they can be entirely drained. This is neces- 

 sary, sometimes, tor cleaning or repairing them, and 

 changing the fish from one pond to another. If the slope 

 of the ground is sufficient to permit of such an arrange- 

 ment, it will often save much labor in pumping or bail- 

 ing. The diain pipe may be of pump logs, tile or pipe 

 of any kind, and should be fixed in the lowest part of the 

 bottom, or as near it as the level of the ground will al- 

 low. Still better would be a regular flujpe reaching 

 from the bottom of the pond to the top. A bulkhead 

 may be put in to raise the water as high as may be re- 

 quired, and a wire screen the wl^ole size of the fiume set 

 a short distance in front of the bulkhead. This large 

 screen has an additional advantage, as the larger the screen 

 the less liable it is to clog up with leaves and moss, and 

 the greater will be the volume of water passing through 

 it. 



ScEEENS. — Screens may be made of common wire 

 painted with tar — as will be described hereafter — of cop- 

 per wire, or of galvanized iron wire. The last is the 

 best, as it will last longest in proportion to its cost. 

 The screens for keeping the small fry should be ot four- 

 teen threads to the inch, and for one year old fish five or 

 six threads to the inch. Incline the screens at an angle 

 of forty-five degrees, the top being farthest down stream. 

 By inclining the screens in this manner a greater surface 

 is exposed to the water than if they were placed perpen- 

 dicularly. The sockets should be so made that the 

 screens will fit tightly and yet be easily taken out to 

 clean. 



