XXIX.-REPORT ON THE PROPAGATION OF SCHOODIC SALMON 



IN 1879-'80. 



By Charles G. Atkins 



1. — Preparations. 



The experience of the preceding season had demonstrated the useful- 

 ness of a developing-house by the side of the stream, and the experi- 

 mental structure of that year was this year replaced by a permanent 

 house of small size, measuring on the ground 18 by 22 feet. Were it 

 necessary to use this house for the hatching of fish, it would be too 

 small to be very effective; but as it is only used to bring a portion of 

 the eggs through the earlier stages, the cold water retarding their de- 

 velopment till, by shipment of earlier lots, room is made for them in 

 the other house, a comparatively large capacity is secured by making 

 the troughs very deep. The principal ones are 17 inches deep inside, 

 accommodating our deepest frames, with 20 trays of eggs in each, and 

 having a capacity of about 35,000 eggs to each foot in length of trough. 

 There will be room for at least eight troughs, with an aggregate capac- 

 ity of 2,500,000, and it is practicable to increase this 50 per cent, by 

 making deeper troughs, and to even double it by submitting to consid- 

 erable inconvenience in the routine work. The supply of water is prac- 

 tically unlimited, and its six-inch conduit now delivers from 60 to 100 

 gallons per minute, according to the head in the stream, which is 

 affected by the rise and fall of a connecting mill-pond used by the tan- 

 nery. The head of the conduit is in the stream, two rods from the 

 shore, and, it is supposed, far enough out to secure a supply of water 

 always pure, just as it comes from the lake. 



Measures were also taken to increase the volume of water at the old 

 hatching-house by laying a log aqueduct to a springy spot 21 rods dis- 

 tant, and 13 or 14 feet above the floor of the troughs; an opportu- 

 nity is thus afforded for aeration, which goes far to make up for the mea- 

 ger volume secured (only a gallon and a half per minute), and makes 

 this an important addition to our supply. 



The experience of the previous season had also suggested a removal 

 of our fixtures for capturing and manipulating the fish to some point 

 above the dam. A very convenient site was found on the west side of 

 the stream opposite the head of the approach to the tannery canal, 230 

 feet above the dam. Here is near a quarter of an acre of shallow water, 



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