THE HABITS OF THE SALMON. 31 



The river may be said to be in two sections divided 

 by a large fall, over which the fish can ascend with 

 considerable difficulty, but not in all sizes of the 

 water. The only sure and safe chance in getting over 

 is when the river is in a middling size, neither too 

 high nor too low. The principal angling during the 

 spring months is from the big fall, as this is called ; 

 for the reason that, about a mile farther down, the 

 river runs over a low ledge of rock, known by the 

 name of the little fall, which from appearance should 

 be no obstruction to the fish at any season ; but it 

 is remarkable that they never go higher up the river 

 than the little fall earlier than April, and whatever 

 size the water rhay be, salmon never attempt to go 

 over the big fall earlier than the middle of May, and 

 very often not before the beginning of June." 



We find, therefore, that on the Shin, Oykel, and 

 Cassley, the temperature has exactly the same effect 

 on salmon moving upwards as it has in other rivers 

 I have already mentioned. On the Cassley and 

 Oykel, which are not fed by big lakes, the fish are 



