8 PRACTICAL CARP CULTURE. 



point in the kettle, so as to insure thorough emptying of the pond. The 

 perforations in this box G H should not exceed a half inch in diameter, 

 and sTioulci be numerous in proportion to the volume of the water entering 

 the pond and passing the overflow;. if necessary, perforations may be 

 made in the side as well as in the front. The total capacity of these per- 

 forations should be considerably greater than the capacity of the hori- 

 zontal box, as in emptying the pond, the holes necessarily become more 

 or less choked by mud, fish, water-plants, etc. 



BOTTOM OVERFLOW AND DRAIN. 



In the upright box C D K I, is framed a perpendicular slide or gate, 

 K. F, which fits tightly on the bottom of the horizontal box A B, the end 

 of gate being held in position by strips nailed on the bottom; similar 

 ntrips, N N, are nailed on the vertical sides of upright box; between 

 which the gate is lifted up or forced down by means of an iron hook or 

 i ing in top of gate at the point where the curved arrow shows water pass- 

 iugover. The course of the water when overflowing is shown by the 

 arrows. 



The pond is emptied by simply lifting the gate E F, when the water 

 passes directly through the horizontal box A B. 



On the top of the upright box at I K is shown a lid which may be 

 locked down, to keep idlers and thieves from raising the gate and empty- 

 ing the pond. 



The water level in the pond op,n be changed at will by simply placing 



