AN IMPROVEMENT IN HATCHING AND REARING BOXES. 



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Fig. I. — Plan. 



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its lower edge being exactly flush with the bottom of the box (fig. i ) . The orifice 

 to which I refer opens into a pipe which is joined to it and runs upward to 

 within an inch of the top of the box, where it turns outward and acts as a spout 

 (fig. 2). The pipe must be of the same dimensions as the circular orifice. In 

 order to prevent the escape of alevins and fry, the orifice where the pipe is fixed 

 into the box should be covered with a grating of fine parallel wires at spaces 

 of about ^ inch apart. The grating may be a little larger, but must on no 

 account be smaller, than the opening of the pipe on which it rests, or the ring to 

 which the wires are soldered will obstruct the passage of any light particles that 

 are being carried away by 

 the outfall. To support 

 the box two semicircularly 

 cut-out boards, placed on 

 edge, will be required 

 when it is placed in the 

 hatchery. These, I should 

 say, are detachable, the 

 box being held in position 

 by its own weight. Fig- 

 ure I will explain the ac- 

 tion of the box. It will 

 be seen that the supply 

 falls in at B and, so far as 

 the surface is concerned, 

 follows the course marked 

 by the arrows, while a cur- 

 rent extending from B to C 

 is caused by the outfall 

 picking up and ejecting 

 any light particles that 

 happen to gravitate within its influence. It is needless for me to add that the 

 box must be fitted with a cover, so that the eggs maybe protected from the 

 effects of the Hght during their period of incubation. 



The furnishing of the box with baskets or with grills, as the case may be, is 

 a matter which must be left to the discretion of the pisciculturist who has to use 

 it. If baskets are decided upon they can be fixed in position exactly as they are 

 in the rectangular hatching box. If, on the other hand, grilles are employed, they 

 can be held in a light iron frame resting on a series of studs projecting from the 

 sides of the box. Next season I hope to have one of these boxes fitted with a 

 set of wire baskets, not more than an inch in height and divided by longitudinal 

 slips into compartments which will take five rows of eggs side by side. The 



Fig. 3. — Cross section. 

 DESIGN OF PROPOSED HATCHING AND REARING BOX. 



