16 



of breeding, no shad, whitefish or salmon trout are used, 

 except those that would be caught and killed by the fisher- 

 man, and salmon eggs are only obtained from rivers 

 teeming with a supply. As for the New York commis- 

 sion we can say no fish are killed purposely to obtain 

 their eggs, and no streams can possibly have been de- 

 pleted by the action of the commission. 



There are certain well marked eras in fish culture in 

 which the main discoveries have been made. Most of 

 the appliances adopted abroad have been abandoned with 

 us, and great strides have been made in developing the 

 art. Our first great discovery was what is known as dry 

 impregnation, that is the use of little or no water in im- 

 pregnating the eggs with the male fluid. This was kept 

 a secret however, from the public until it was re-discover- 

 ed in Russia. Here it was first practiced in 1864, and up 

 to that time twenty-five per cent, of the eggs was the 

 greatest number impregnated ; immediately afterwards 

 the proportion rose to seventy-five per cent, and is now 

 ninety eight. At present " dry impregnation " is univer- 

 sally adopted. The next great discovery in appliances 

 was the shad hatching box, which has never been super- 

 ceded for certain classes of fishes and situations, nor has it 

 been improved on since it was invented. Another seem- 

 ingly trivial but extremely important discovery was the 

 application of coal tar as a coating to wood work and all 

 articles that come in contact with the eggs, and on which 

 fungus could do harm by growing. The last was 

 the invention of the Holton hatching box for hatching 

 whitefish, but which is a valuable convenience in manag- 

 ing the eggs of all the salmon and trout. These discover- 

 ies have reduced the labor and expense of fishculture im- 

 mensely, and have added in an equal degree to efficiency 

 and certainty oi success. 



