200 SEASON 1875-76. 



a large number will get their physiognomy distorted, and their 

 lower jaw dislocated by frequent contact with the guard. 



The fish were afterwards found apt to jump over the trough, 

 on the screens of which they often lay in great numbers. I there- 

 fore fixed a frame of zinc round the inlet of the pond ; this has 

 answered well. The outlet was guarded by a screen designed to 

 pass the water freely in frost, and it has acted thoroughly with one 

 foot of ice on the pond. The frame is made of batten, and a groove 

 is cut for the screen. The frame is merely planted on the end of the 

 pond, so as to cover the outlet, and, being much deeper, it reaches 

 considerably below the bottom of the outlet ; and the water has 

 always a clear space to pass the screen below the ice, and the 

 current it makes passing up the end of the pond to the outlet is 

 sufficient to prevent the ice forming. Fig. 150 is a plan of the pond. 



The thin sheet of water falling into this pond the whole 

 length of the end has been found an excellent plan, and I can keep 

 a much larger stock of fish in this pond than in any other pond I 

 have yet built proportionately to its size ; and not only a larger 

 stock, but I can with safety keep trout of eight years of age, and up 

 to 6 Ibs. weight. It seems, therefore, that, with perfect aeration of 

 the water, a much less depth will suffice ; but it is plain that in most 

 cases it is cheaper to make ponds deep than to give this amount 

 of aeration ; and if the supply ever becomes light, the fish in the 

 deeper ponds are in hot weather safer than those in the shallower. 



A 12 -inch pipe brought the water from the intake to a trough 

 at the head, and to one side of the 20-feets. The trough feeding 

 the 20-feets was joined at right angles to this aqueduct, so that the 

 water from the 10 -inch could be added to that from the 12-inch if 

 required. This aqueduct was closed at its lower end, and a 10-inch 

 pipe fitted taking water past the 60-feet pond. A T-piece was 

 built, into which the trough feeding the 60-feet was led, and a 

 board in the end was cut to supply the 10 -inch, but so as to give 

 the 60-feet the first of the water, the 10-inch only getting the 

 surplus. Of course, as the supply to the aqueduct was a 12 -inch, 

 the 10-inch was nearly full after the 60-feet had a sufficient supply. 



A pipe (10-inch) was also led from the troughs, catching the 



