208 SALMONIA. 



40, the degree at which water is heaviest I 

 see no reason why grayling may not be ha- 

 bituated to such a temperature, coolness 

 being generally favourable to their exist- 

 ence. But see, the fog which had filled the 

 valley and hid the mountains from our sight 

 is clearing away, and I fear it will be a hot 

 day. Before the sun becomes too bright is 

 the best time for fishing in such a day as this. 

 As soon as the fog is fairly off, the water- 

 flies will begin to appear, and fish to sport. 



PHYS. I see the fog has already disap- 

 peared from the deep water in the meadow, 

 where I suppose the warmth of the air from 

 the considerable mass of the water is greater ; 

 and which is further removed from the hills 

 sending down currents of cold air, from the 

 mixture of which with the moist warm air 

 above the river this phenomenon is produced. 

 I see some yellow flies beginning to come 

 qut ; they have already felt the influence of 

 the warm air : and look ! a fish has just risen 

 opposite that bank, and he rises again : let 

 us prepare our tackle. 



POIET. What flies shall we employ ? 



HAL. I recommend at least three; for 



