.104 Fish, Fishing and Fisheries of Pennsylvania. 



egencies of both dam and river, and at the same time it must provide 

 for the erratic requirements of the fish. 



In all the applications, the entrance is located close to the dam, where 

 the fish, instinctively searching for a passage to the river above, most 

 naturally linger. This feature is a most important and commendable 

 one, and to it is largely due its unprecedented success. 



The interior arrangement is very simple, consisting of a sluice-way 

 five feet wide by three feet deep, running at a grade of about one foot 

 in nine or ten, provided with a series of fences (called buckets) set at 

 acute angles on either side, leaving openings of fourteen inches, allow- 

 ing for the passage of a sufiicient volume of water to accommodate the 

 largest river fish. These buckets so retard the water that its force is 

 reduced to a minimum, and the arrangement is so perfect that at what- 

 ever the height of the obstruction, or whatever the length of the fish- 

 way, the current is no stronger at the bottom than at the top. 



The fishway proper is built solidly within square timber crib-work, 

 bolted to the bed-rock and to the dam and heavily ballasted with stone, 

 the whole being substantially covered with heavy plank, except the 

 lower side of the crib, through which the light is allowed to enter. 

 Against the small projecting portion at the head is provided a substan- 

 tial ice-head, which is given an easy slope, thus presenting little resist- 

 ance to the ice. A breakwater is also provided, which renders the en- 

 trance clear from falling water. 



In fact, so perfectly are all the requirements met, and so completely 

 has Mr. Rogers overcome the many heretofore existing difficulties, that 

 there is nothing further to be desired in a fishway. 



The comparatively small cost of construction is another commendable 

 feature, it being principally guided by the market prices of the materials 

 used and by the obstruction to be overcome. 



Briefly summed up, its strong features are: 



1. Applicable to any form of dam or natural fall. 



2. The entrance is near the dam, where fish accumulate in search of 

 a passage to the water above. 



3. The stream is as near a natural brook as can be produced. 



4. The current is easy — just strong enough to be an attraction to 

 fish. 



5. Bach bucket forms a pool such as fish delight to play in. 



6. It draws a very small quantity of water, and this can be shut off 

 at any time if found necessary. 



7. It is thoroughly ice proof. 



8. Not liable to clog up, requiring only ordinary care, as small debris 

 can pass through very readily and large matter cannot enter. 



9. Repairs are seldom necessary when properly built at first. 



10. Never known to injure a dam or water power in the slightest de- 

 gree, but, on the contrary, it is a support to the dam. 



