14 THE DRY FLY AND FAST WATER 



one time covered the hills through which they 

 have their course. During the frequent and 

 long-continued droughts the denuded hills, baked 

 hard as rock, shed the occasional summer showers 

 as readily as the back of the proverbial duck; 

 the streams become turbid torrents for a few 

 hours, after which they run down, seemingly to 

 a lower mark than before. So long as the forests 

 covered the watersheds the rains as they fell 

 were soaked up by the loose and porous earth 

 about the roots of the trees, were cooled in the 

 shade of the leaves and branches, and slowly 

 percolated into the tiny brooklets through 

 which they were fed to the streams for many 

 days. Under present conditions the tempera- 

 ture of the streams is much higher than for- 

 merly, and, while the temperature has seldom 

 risen to a point where it has been fatal to the 

 fish, it has risen in many streams to a point 

 that is distasteful to the native brook-trout 

 (Salvelinus fontinalis). 



It is not unreasonable to assume that the 

 heat of the water has a very deleterious effect 

 upon the vitality of the fish during certain 

 years when the droughts are long sustained 

 and, should the condition have existed for a 

 great length of time prior to the spawning sea- 



