210 BULLETIN OP THE UNITED STATES FISH COMMISSION. 



floor of the ladder. The ladder rests on strong beams [h), and is kept in 

 its place by several small posts (t), which are let into the beams. Its up- 

 per end is supported by the wood- work [Ic I), and the lower by the float 

 or platform (n). The wood-work {Ic I), close to the front of the dam (c), is 

 lower than the dam edge, and consists of the two piles (A-) and the sup- 

 porting beam (?) mortised on to them. The beam is fastened to weir by 

 strong iron clami)s {m, 1 inch square), which go through it, and are se- 

 cured by nuts or screw ends underneath. On this support [l) the up- 

 per end of the ladder rests free, so that its floor is level with the top of 

 the weir, and just touching it, while the sides of the ladder are higher, 

 so that the water can flow down between them. The ends of the sides 



Anton Pintsch's movable fishway. 



(/,/), where they meet the ends of the guides {v, v), are cut at angles 

 (see illustration) to . permit of the ladder working in its place, as the 

 platform rises or falls. The small space between the ladder (d) and the 

 edge of the dam {b) can be covered by a board nailed to the dam, if it 

 was necessary to prevent any water falling through. 



The i)latform {n) floats on the surface of the water, and is held fast 

 by the two bars {s s) which are fastened to hooks in the weir and plat- 

 form. The platform is formed of several 8-iuch to 9-inch logs of well- 

 seasoned wood (n). These are fastened together by the stout piece (r), 

 on which rests the cross-beam (o), the ladder being kept in place by 

 nails in the supports {p), which act as axles on which it works. The 



