286 SALMON FISHING 



pushing through the steep gradient at the top, the 

 spread-out water at the bottom is too shallow for 

 them to cross. When the river is high, the fish are 

 unable to stem the current at the top of the fall. 

 A pass of somewhat similar kind is to be seen on 

 the Don at Mugie Moss. It is a channel, cut in the 

 middle of the weir, with a smooth bottom and a 

 steep gradient. The water comes down at such a 

 pace that when they are half-way up the salmon are 

 thrown back. They would have a better chance if 

 the pass were closed and the water allowed to 

 go over the weir, below which, as I write, many 

 hundreds of salmon are probably being taken by 

 the net. This state of things should not be allowed 

 to go on. It robs the proprietors above, and deprives 

 the proprietors below of the increase that would 

 arise if the fish were allowed to go forward. Another 

 dreadful example is the Macdonal fish -way on the 

 Ericht at Blairgowrie. That is an American scheme 

 accomplished at great cost. Not a single fish has 

 ever been known to pass that way. The four passes 

 at the outlet of Loch Vennachar, erected by a well- 

 known engineer forty years ago, were beautiful in 

 design and in workmanship, but they were a failure. 

 The gradient was too steep. Many another pass is 

 merely a slap in the weir, a slap a few inches deep. 

 Now, a weir, as a rule, is from two to three times the 

 average width of the river, and a large quantity of 

 water is taken away in the mill lead. The con- 

 sequence is that the water in the pass is so thin that 

 salmon cannot get through it at any time of the 



