•20 



Appendices to Twenty-eighth Annual Report 



Conclusions. 



At comparatively low obstructions, such as dam dykes and small falls, a 

 pass may conveniently be of uniform gradient, provided the gradient is 

 easy and the entrance for fish is suitably placed. At the same time, the 

 formation of pools instead of a single chute-like pass is often advisable. 

 At high falls, where the pass requires to be long, the most satisfactory 

 results, in my opinion, will be obtained by the free use of pools. If the 

 gradient requires at any point to be steep, the Torrbol type of pool is to be 

 recommended ; where the gradient may be easy, and especially where a 

 large flow of water has to be dealt with, I would advocate the Kingairloch 

 type of pool. 



