924 THE AMERICAN FARMER 



would be as well to have the windows, if possible, made on the north side of the hatching 

 house, into which the sun will not shine in the winter season. Keep the hatching house 

 clean. In fact cleanliness is one of the cardinal virtues to the trout raiser. He should have 

 a clean house, should work with clean hands, and have all his pans, spoons, and utensils of 

 every sort free from grease and dirt. 



Troughs. These should be made of seasoned timber one and a half inches thick. They 

 should be six inches deep and about fifteen inches wide, inside measurement. It would be 

 better, perhaps, if the troughs were eight or nine inches deep, because then the water could 

 be raised higher over the young trout after they are hatched out. The difficulty in making 

 them so deep is that when the sides of the trough are made so wide they are apt to warp or 

 stretch apart at the top, and must be stayed in some way ; for instance, by strips nailed across. 

 But the cleaner the trough is of all strips, elbows, or grooves the better. The troughs are 

 divided into squares or nests by cross strips set on the bottom at intervals of eighteen inches. 

 The reason for this division into nests and for these cross strips will be seen further on. 

 These strips may be made of half-inch stuff and cut two inches in width. There is no neces 

 sity for nailing them to the bottom ; fit them in accurately and set them edgeways at intervals 

 of eighteen inches. As they do not need to be removed often, it is better to make them fit 

 tightly. Other strips of the same stuff must be provided to fit upon these, and made wide 

 enough to raise the water within an inch of the top of the trough; as these need to be often 

 moved they must be made loose enough to take out, and yet fit accurately enough to raise 

 the water over them when they are put in. A groove is sometimes made in which to run the 

 strips, or shoulders nailed to the sides against which to set them, but it interferes with the 

 equable flow of the water. New wood under the action of water develops a slimy sap, there 

 fore it is necessary to paint the troughs with hot coal tar mixed with enough turpentine to 

 thin it to about the consistency of paint. Glass has been used to cover them, and the wood 

 has been charred to prevent the growth of fungus, but nothing answers so well as gas tar, 

 which should be used to cover every thing in the troughs or ponds, and where fungus can do 

 harm. The troughs should have an inclination of about one inch in eight feet just enough 

 to let the water ripple gently over the cross strips. They should not be longer than twenty 

 feet, or the air in the water will be exhausted before the water reaches the end of the trough. 

 There is more danger of this after the eggs are hatched out and the troughs are full of young 

 fish. If possible the hatching house should be so far below the level of the spring from 

 which its supply of water is derived, as to allow the troughs to be raised two or three feet 

 from the floor. Where a large number of eggs are to be hatched, the inconvenience of stoop 

 ing to care for them is very great. 



Water Supply. From the filter, the water runs into the distributing trough or pipe, 

 which runs along the head of all the hatching troughs. The water may be let into the hatch 

 ing troughs by faucets, or through holes cut into the trough. These holes should be covered 

 with netting, or the young fish will run up out of the troughs into the filter, or coarse gravel 

 may be heaped up at the head of the trough through which the water will run, but through 

 which the young fish cannot work their way. The supply of water for one trough should be 

 equal to that coming through a three-fourth-inch hole with three inches head ; just enough to 

 make a gentle ripple over the cross-pieces. Be careful to get the troughs level crossways, 

 and the strips true, so that when the water is running, it will form an equal current over 

 every part of each strip along the whole length of the trough. If the water runs unevenly, 

 the eggs will be washed into a heap if they are being hatched on gravel, and many of them 

 spoiled for lack of proper circulation of water around them. This supply of water will be 

 sufficient until the eggs are hatched out, when a somewhat larger supply can be allowed. 

 The water should be brought directly from the spring in a pipe of some kind, in order to 

 preserve the proper temperature and keep the water as free from sediment as possible; and 

 for the same reason the spring should be walled up to its smallest possible dimensions. If 

 any surface water naturally runs into the spring, a ditch should be dug around the spring to 

 lead it off. If the muddy surface water is suffered to run into the spring which supplies the 

 troughs, the screen will very soon be choked up, and the sediment will find its way into the 

 troughs in spite of all precautions, and destroy the eggs. 



Filter i The filter is a box six feet long by one and a half feet wide, and one and one-half 

 feet deep, in which four or five flannel screens can be placed through which to filter the water 

 before it passes into the troughs. The coarsest and cheapest red flannel is the best. It will 

 rot and must be renewed once or twice in a season. Red flannel will last twice as long as 



