A NEW FORM OF FISHWAY. 



By Professor Edward E. Prince, LL. D., D. Sc. 



Dominion Commissioner of Fisheries, Ottawa, Canada. 



The principle upon which fishways or fish-passes have been 

 constructed in the past has been by arranging the gradient so as 

 to enable fish to ascend from a lower level to a higher level, and 

 thus surmount water-falls, dams, and other obstructions. The 

 greater the height of the obstruction, the steeper, or the longer, 

 the gradient requires to be, and the head of water, or the force 

 and amount of water, permitted to pass through the fishway 

 requires to be varied to suit the different kinds of migratory fish 

 passing up. 



EXISTING FISH-WAYS UNSUITABLE FOR ALL FISH. 



Each species of fish has its own climbing peculiarities, as it 

 were, and the fish-pass which would suit one kind of fish may 

 not suit another, shad and gaspereaux or alewives being altogether 

 different from salmon or sturgeon. There have been fishways in 

 Canada which proved successful for salmon, but the force of the 

 water killed the weaker fish, such as alewives or smelts. The force 

 of the water knocked these feebler fish against the compartments, 

 and dead fish were often found, proving the utter unsuitability of 

 the fishway for the different kinds of fish attempting to ascend 

 it. Such fishways, as the McDonald fish-pass, endeavored to 

 get over this difficulty of momentum, or force of water, by devices 

 which broke the force and reduced the momentum, but as a rule 

 the introduction of complicated arrangements for this purpose 

 resulted in the accumulation of rubbish, and caused other diffi- 

 culties, so that the structure was often rendered useless. 



My new fishway, which has been tested experimentally in 

 Canada with every evidence of success, adopts the principle of 

 the perpendicular elevator, and if the fish can be induced to enter 

 it, there is no doubt that it will lift them to the top of the 

 obstruction. 



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