ARTIFICIAL HATCHING OF FISH. 49 



large tank into which the water flows before enter- 

 ing the hatchery. This gives the impurities a 

 chance to settle at the bottom, and the water will 

 become purer ; and when it afterward flows through 

 the flannel screens, it is purified to a still greater ex- 

 tent. But, even with these precautions, a great deal 

 of sediment will force itself through into the hatch- 

 ing apparatus, and the eggs have to be looked over 

 and feathered nearly every day in order to keep 

 them bright and clean. The hatching apparatus it- 

 self needs frequent washing to keep it free from the 

 matter which accumulates on it. Without scrupu- 

 lous cleanliness, artificial propagation would not, in 

 this respect, be superior to the natural. 



CAREFUL HANDLING. This, in my opinion, is a 

 most important consideration, and one that cannot 

 be over-estimated. Some persons claim that there 

 are stages in the development of the eggs when 

 they can be handled very roughly, and will stand a 

 great deal of abuse without injury. This is con- 

 trary to my experience. From the time the egg is 

 first taken, until it is hatched, the utmost caution 

 should be taken to prevent any ill-usage. While 

 there is undoubtedly a certain period when the eggs 

 are less liable to be killed by exposure to some 

 amount of hardship than at other times, still, I find 

 that the most careful treatment given them is none 

 too good ; and the more gentle we are with them 

 the larger percentage of strong and vigorous fish 

 breaks through the shell of the egg. Even in 

 "feathering " them over with the beardecl side of a 

 feather in search for dead eggs, it would be better if 

 the eggs were not touched, but simply moved by 



