96 VEKMONT AGRICULTURAL REPORT. 



hatchery is dependent upon it. As this article contemplates the 

 necessity for only a small floor space to hatch enough fish to stock 

 one stream or a portion of it, room for the hatchery may be found 

 in the barn, barn cellar, cellar of house or some other available 

 space protected from the inclemency of the weather. Assuming 

 that there is floor space somewhere about your buildings, can you 

 run your present water supply into it and have you sufficient flow 

 of water to spare some of it for fish cultural purposes ? A consid- 

 eration of the following requisites will enable you to decide. 

 First, the supply can be from a spring, a brook, a pond or a lake. 

 Fish culturists differ as to which is preferable, but conditions 

 vary in different localities and climates. In Vermont, very few 

 brooks are free from sediment at all seasons. Springs, if tapped 

 at their sources, are practically free from sediment and give 

 au even temperature. Perhaps it would be well to make it the 

 first condition that the water must be free from sediment. That 

 is, it must not become roilly during the frequent thaws in winter, 

 or the heavy rains of spring time. Second, it should be of an 

 even temperature throughout the period of incubation. This 

 last is not essential, but preferable. In our climate, the normal 

 temperature of spring water at the source of springs is 46 to 48 

 degrees and does not vary from that amount summer or winter 

 more than five degrees. If allowed to flow along the surface 

 until it forms into a brook, the temperature will of course be re- 

 duced in winter and raised in summer, but will be comparatively 

 even. Trout eggs can be hatched in any temperature of spring 

 water, or in a temperature varing from 33 to 50 degrees Fahren- 

 heit. I prefer a temperature of from 36 to 44 degrees during 

 the period of incubation, rising to 60 or 65 degrees for the little 

 fishes as warm weather approaches. Ordinarily, the water sup- 

 ply for a house and stable is suitable for this work if a sufficient 

 volume of it can be spared to flow steadily, 24 hours a day, for 

 every day the hatchery is in operation. A city water supply 

 can usually be regarded as suitable. Trout cannot be hatched 

 successfully unless the eggs have a constant flow of water. It 

 cannot be diverted temporarily for creamery or domestic purposes 

 without danger of weakening the eggs. The quantity of water 

 depends upon the number of eggs to be hatched or the number 

 of hatching troughs to be used. The minimum amount of 

 water allowable for one trough whether to contain 10,000 

 eggs or double that number, should not be less than two gallons 

 per minute. The simplest way of ascertaining whether there 

 is a sufficient flow of water is to catch the flow in a pail of known 

 measure and see how long it takes to fill the pail. If you have 

 a spring of unknown volume, put in a temporary spout with 

 earth packed around the intake end, long enough to conduct the 

 water to a point where it can be caught and measured. Do not 



