-.to^ qptain it. 



Each hatching box must be provided with a screen, which 

 consists of a charred wooden frame covered with perforated zinc 

 (No. 7 zinc is. a good size). This screen slides in a groove, made 

 by cutting a strip out of the sides of the hatching box as shown by 

 the dotted lines p c in Fig. 7. This groove is made, of course, on 

 the insides of the box, and should be carefully charred. A piece 

 of flannel should be placed between the screen and the box, and 

 .great care must be. taken that it fits perfectly tight, and that no 

 newly-hatched fish can get through, anywhere. . If it be by any 

 means possible, most assuredly they will. Rests require to be put 

 in along the insides of the box for the grilles. I have, tried many 

 plans, but find nothing better than small galvanized staples, which 

 take up little room, do not make cornersTnto which the fish can 



get, and are not much in the way at any time, when not occupied 

 by the grilles. They should be varnished. I have used inch 

 wire nails driven in half of their length, but I like the staples 

 better. 



All wooden hatching apparatus should be carbonized wherever 

 the water comes in contact with it. Elsewhere it may be painted. 

 The carbonizing, or charring as it is commonly called, is done by 

 working hot irons over the surface of the wood. The bigger the 

 iron the longer it keeps hot, but the greater amount of heating it 

 requires to make it hot enough. It often happens that at a 

 hatchery a very large fire is inconvenient, and, therefore, it is better 

 to have comparatively small irons. To begin with, procure from 

 an ironmonger two of the largest ordinary " flat irons " that are in 

 general use. They will be found to do the work well, and are 



