Jak. 19, 1888.] 



FOREST AND STREAM. 



507 



FIG. 2. 



DIAGRAM OF THE ROGERS PATENT FISHWAY AND AUXILIARY DAM. 



(Tite basis of the above diagram Is the TTolyokc dam in Massachusetts.) 



Via. 1 is a general plan of arrangement. Fig. 2 is a vertical sectional view of same. 

 Like letters denote the same parts in both figures. 



A A represents top of main dam. B, inner face of same. G, lower face, over which the flood ol 

 water pours. P, position in which it would he proper to place a fish way where practicable. F, a 

 canal built to carry water from pond above down to mills, etc., below. H ft, rates by which the flow 

 of water may be regulated. L, the auxiliary dam, built below main clam. N, lower face of auxiliary 

 dam where fish are stayed in their progress up stream. K, a wire fence used in some cases for same 

 purpose, where the water has not too much force to prevent its security. M M, wings of same, for 

 turning fish in any required direction. B, fishway, with an entrance into the canal ('this fishway 

 may be carried ut> around any dam or cliff, as desired). 6. the wall or bunk which separates the 

 water in the canal from the river and holds it at the level of the headwaters, ft, bed of river where 

 fish come up. J J", foot of fish ways, showing the open mouths at the face of the auxiliary dams. 

 I, outlet from fishway to headwaters, or inlet of water from pond above. 



Fig. 2.—0, level of water in pond above main obstruction in river. Go, level of top of main dam. 

 A. cop of sectional drawing of main dam. B, upper slope. (.', front face. D, body of main dam. 

 P, where fishway should be placed when practicable, ft, river bottom. 8, section of auxiliary dam. 

 i, back slope. JV\ front or down stream fare— the obstruction presented to fish, thus preventing 

 them from passing the foot of fishway and turning them into it. H, fishway in position. Hh, side of 

 fishway. 



THE ROGERS PATENT FISHW 



Bird's-eye view, showing interior and fish ascending. The top of the structure is, of 

 course, to be covered in by heavy timber for protection against ice 

 and freshets— spaces being left to admit the light. 



