FISH CULTURE. 935 



to place them. Put them into still water; they will settle down on the bottom, and remain 

 there for some hours; then they will begin to explore their new quarters, and in a few days 

 will become thoroughly habituated to the place. 



Boards are sometimes placed over the outer edges of the preserves to give the fish a 

 hiding place and shelter from the sun when they wish it, and, more important than all, to act 

 as a trap for minks in case there is danger of these destructive creatures getting into the 

 ponds; as the boards project nine or ten inches from the sides, if a mink gets in he cannot 

 make his way out. 



Where a large number of fry are hatched they have to be left in the troughs until they 

 can be distributed, which is done as soon after the absorption of the sac as possible. In this 

 case the troughs must have all the gravel removed, and must be kept scrupulously clean. A 

 very little decayed meat will render the water offensive, and produce disease. This offen- 

 siveness does not show itself in the least in the appearance of the water, which to the eye 

 may be as bright, clean, and sparkling as ever. It can, however, be often detected by the 

 smell. When gravel has been for some time in the tanks or troughs where fish are fed, even 

 with the utmost care, if a handful is taken up it will be found to be very offensive to the 

 olfactories. As well might we expect the human race to be healthy in foul atmosphere as 

 fish to be healthy in foul water. In the ponds it will sometimes answer to cover up or 

 deodorize the feculent matter by throwing earth mixed with a little salt into the water 

 and allowing it to settle; this not only covers the decaying substances, but disinfects them in 

 a measure, on the principle that dry earth is used in the earth closet. The water is to be 

 made quite thick and muddy with the earth, and the operation is to be renewed every few 

 days, as often as necessary. The roiliness of the water does not seem to injure the fish. 

 This, however, at best is but a makeshift, and the true plan, especially with young fry, is to 

 keep the troughs clean. 



Cleaning the troughs must be performed daily, in the morning and evening. A thin 

 board, nearly as wide as the trough and shaped like a hand shovel, is made with a short stick 

 for a handle nailed across it. When this is held in the water across the trough, it creates a 

 strong current under it. It is held in the left hand, while in the right hand is a small brush 

 broom, such as is used in cleaning sinks, and with which the sides and bottom of the trough 

 are well scrubbed. All the dirt is sucked under the board, and carried along to the lower 

 end of the trough. The fish ai-e also crowded together ahead of the cleaning operation and 

 out of the way of the broom. When the lower part is reached, the fry are driven above, and 

 the operation completed by netting out the larger pieces of meat or dirt, and by rubbing the 

 finer particles through the screen at the lower end of the trough;* or a high cross bar may be 

 put in, the screen raised for a moment, and the waste plug opened. 



When there is not accommodation in the troughs for all the fry, and they cannot be dis 

 tributed, a temporary place of retention may be made by using the shad boxes, which are 

 described under the chapter on shad hatching. They need not generally be set at an angle 

 to the current, as the mere ordinary disturbance of the water near the outlet of the ponds 

 will give them motion enough to change the water. These will answer only temporarily, and 

 must be cleaned as carefully as the troughs. They are to be scrubbed all over the inside and 

 on the bottom. To do this without injuring the fish, the box is tipped up so as to bring one 

 part after the other out of the water, where it can be brushed, while the fry are safely 

 swimming at the other end. 



If the- fry must be kept in confinement, absolute cleanliness is a necessary prerequisite to 

 their health; but we cannot too strongly impress upon our readers the desirability of 

 turning them into the small rivulets connected with the waters where they are to live, as 

 soon as possible after the sac is absorbed. Although they encounter some perils to which 

 they are not exposed if kept in preserves, they escape still more dangers and acquire the 

 habit of taking care of themselves, which is necessary when they come finally to be thrown 

 upon tneir own resources. 



Food of Fry. The best food for trout fry is raw liver, chopped as fine as possible, and 

 then rubbed through a screen or sieve with a flat stick. It must be reduced to the con 

 sistency of pulp, and contain no strings or gristle. A chopping machine is made for chopping 

 hash and sausage, and either that, or a couple of sharp knives are used to chop the liver. 

 What is used is mixed with water so as to reduce it to about the thickness of cream. A tea 

 cup full of this mixture will feed a hundred thousand fish when they first begin to feed. The 

 best way to feed them is to take a case-knife, dip it into the food and slirt off what adheres 

 into the troughs; a very simple way, but one answering all practical purposes. Care should 



