PROPAGATION OF FISH. 247 



been sent until the troughs are ready for them. Persons 

 will sometimes take the tin boxes containing the eggs out 

 of the sawdust in which they were packed, and set them 

 in the water of their troughs, with the idea perhaps of 

 getting the eggs in the box to the same temperature as 

 the water before unpacking them. This will surely kill 

 the eggs in a few hours. Leave them in the original pack- 

 age until a few hours before you are ready to place them 

 in the troughs. Then take out the tins and set them 

 over or near the troughs, which will reduce or raise the 

 temperature enough. Then empty the box into a tin pan 

 full of water taken from the trough, pick out as much 

 moss as you can readily with your fingers or nippers, and 

 wash off the rest in the manner shown in directions for 

 washing eggs hereafter. 



The eggs are placed on trays made of wire cloth 

 stretched on wooden frames. Each tray is twenty-seven 

 inches long by fourteen inches wide, and will hold in a 

 layer, one deep, six thousand two hundred and seventy- 

 two salmon trout eggs. Instead of using only one layer 

 of these trays, it has been the practice of late years to use 

 four layers in the upper sections and five in the lower 

 sections. 



If only a few eggs are to be hatched (say eight or ten 

 thousand) no hatching house is necessary. The troughs 

 may be placed in the open air, in any convenient place, 

 and covered with a wire screen, to keep out rats, mice 

 and ducks. A light board cover must then be laid over 

 them, to shed the rain and snow and keep the eggs from 

 exposure to the sunlight. A hatching house is much more 

 comfortable to work in. A stove may be put in it and a 

 fire started occasionally for warming one's fingers, but it 



