24 



PRACTICAL OABP CULTURE. 



while, no doubt, poisonous gases had much to do with it, it is just as cer- 

 tain that lack of deep water also had much to do with. it. 



To obtain both shallow and deep water, on about one-half of the area 

 of the pond around its edges the water should be from nothing to eighteen 

 inches deep; on about one-fourth of the area of the pond, from eighteen 

 inches to three feet deep, and on the other one-fourth, from three feet to 

 eight or ten, or even twelve feet deep, the greatest depth being at the 

 point where the drain-pipe and collector are situated, as shown in the 

 accompanying illustration: 



LONGITUDINAL SECTION OF A POND. 



J is the Inlet or point where the water enters the pond ; E is the spawn- 

 ing ground for the fish, and is shallow and full of water plants; S is the 

 surface of the water; L is pond lillies to give shade to the fish in hot 

 weather; C is the collector, or deepest point in the pond, and is situated 

 at the entrance of the drain-pipe. O L is the outlet passing under the 

 dam from the lowest point in the pond bottom; J5Tis a collector situated 

 outside of the dam to trap any fish that may possibly escape through OL; 

 D is a cross section of the dam. The bottom should be of a uniform 

 grade, sloping from all points to the collector. A ditch, four feet wide and 

 two feet deep, leading half the length of the pond and down to the col- 

 lector, will, when drawing off the pond, greatly facilitate the bringing of 

 the fi.Hh to the collector Side ditches, tapping any low spots in the bot- 

 tom, should be run into this leader. It serves a further purpose in getting 

 below the gas-producing stratum of the bottom, and in just that degree 

 preserves the fish in winter from its influence, as the gas rises to the ice 

 and saturates the water from the ice downward. 



All artificial ponds should be so constructed that they can be drained. 

 It is quite indispensable to successful pond culture. In Germany, with 

 the experience of centuries in carp culture, their system of draining 

 ponds is so complete that they rotate carp culture and agriculture as we 

 do crops, and one helps the other. The bottoms of ponds, in which fish 

 have been raised a few years, make rich fields, and cultivating the ground 

 a few years again makes it produce more food for t.ie fish. Whatever the 

 advantage arising from the power to drain ponds for this purpose, it is 

 certainly much more essential in enabling you to gather your harvest of 

 fish. 



Of all the plans, systems and methods of draining ponds in vogue, 

 both in Germany and America, the most popular aad the simplest mofebo'd 



