218 TRAVELLING PACE OF SALMON. 



they travel northwards, and of course on their 

 return their road runs south. 



The travelling pace of salmon is slow, between 

 two and three miles an hour. When they meet 

 with rough streams and violent rapids they travel 

 much faster, because if they did not call into ac- 

 tion the full propelling powers of their fins they 

 could not stem rapidly running waters. Before 

 they hazard a trial of strength with the obstruct- 

 ing force of rapids and swift streams they take 

 rest in some easy pool below, and this delay makes 

 their average rate of progress be, whilst they are 

 actually travelling, about two and a half miles an 

 hour. I must here observe that in the spring 

 months the locomotive powers of salmon are less 

 by one half than in the summer months. When 

 the temperature of the water is 70° salmon travel 

 twice as fast as they do when the water's tem- 

 perature is as low as 30°. 



On re-entering their native rivers, salmon ge- 

 nerally repose themselves in the first deep pool 

 they come to. It may be now said that their 

 great voyage is terminated, as they afterwards 

 travel by very easy relays. If one day they are 

 obliged to shoot with rapidity through strong 

 currents, on the next they will take their ease in 

 quiet water. After the month of June salmon 



