WATER CULTURE COMPARED WITH LAND CULTURE. 229 



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 sides with the hand. And in this operation a wonderful advance 



has been made within the last year. Heretofore it was the custom 

 to fill the pans with the water, as this was supposed to most nearly 

 resemble the natural method ; but now little or no water is used, it 

 being found that water drowns the spermatozoa or life principle of 

 the milt. This change of practice alone has made a difference of 

 fully twenty per cent, of the yield, as it is found that the impreg- 

 nation is far more certain by this plan. Care must be taken, how- 

 ever, that the fish are entirely ripe, and that the eggs will run out 

 under a slight pressure ; if they will not the fish is returned to the 

 water till it is in proper condition. 



The eggs are left for half an hour undisturbed, and then are 

 washed and spread in troughs which are filled to the depth of an 

 inch with clean pebbles, and through which flows a gentle current 

 of filtered spring water, and there they remain away from fowls 

 and fish and bugs, safe from sediment and fungus till they hatch. 

 They only require occasional examination for the purpose of pre- 

 venting the collection of deleterious matter, and to remove such as 

 may die and endanger the others. When they hatch they are left 

 in the troughs till the umbilical sack is absorbed, when they are 

 placed in ponds and fed on beef liver, finely grated. Under this 

 management all the serious perils of the natural method are averted 

 and the difierence in the result is almost incredible, being little 

 less than a thousand to one. 



These directions apply to all the salmon tribe — the salmon, 

 the trout, the salmon-trout and the white-fish, all of which have 

 the same peculiarities. To explain the process more fully, I will 

 quote from the report of the New York commissioners of fisheries, 

 presented to the Legislature of that State March 19, 1872 : 



" Stale Hat ching- House. By the last amendment to the act of 

 the Legislature, concerning the protection of fish in this State, 

 the commissioners of fisheries were authorized to build a State 

 hatching establishment for the purpose of breeding the better 

 kinds of fish for distribution throughout the waters of the State. 

 This building was erected during the summer of 1870, and was 

 completed in time for use in the artificial incubation of salmon- 

 trout and white-fish. It is neither a very large nor a very costly 

 establishment, but is the most efficient, practically, and the most 

 productive in results of any in the world. The water is intro- 

 duced in the ordinary way, through a number of flannel sieves, and 

 is led into twenty-four troughs, which are sixteen feet in length 

 by fifteen inches in the clear in width. These troughs are raised 

 about two feet from the ground, so that a person sitting on a stool 

 alongside of them can readily examine the condition of the ova 



