HATCHING APPARATUS. 49 



because your hatching boxes themselves are well 

 guarded from it. It may grow in the aqueduct and 

 be borne down by the stream, and before winter is 

 over, you may find, to your dismay, that it has fastened 

 its fatal grasp on your eggs. If so, they are ruined. 

 There is no remedy for fungus which will make 

 healthy fish of the eggs attacked. They may hatch, 

 but the young fish will be good for nothing to raise. 

 Therefore begin at the beginning, and guard your eggs 

 from fungus by charring the aqueduct. 



3. As a rule, it is best to have the aqueduct covered, 

 but beware of making the outlet end smaller than the 

 inlet end, for then, if anything gets into the pipe too 

 large to pass through the outlet, it will stop the water, 

 and your eggs will be ruined. I have known great 

 danger and actual loss to come from such a defective 

 aqueduct. In one instance a frog got into the pipe, 

 in another a muskrat, in another a cork ; each of which 

 came very near shutting off the water altogether and 

 doing very great mischief. For further safety, put a 

 coarse, galvanized-iron screen over the end of the 

 aqueduct which receives the water. 



4. If you have a small stream, and must convey it 

 a considerable distance, and want to economize any- 

 thing in temperature, you can keep it a little warmer 

 by boxing up the aqueduct itself. But as a general 

 thing it is labor wasted. You will be astonished 

 to see how little any considerable stream changes 

 in temperature in passing through even a long closed 

 spout. 



At the writer's works at Charlestown, N. H., when 

 3 ^ 



