96 HOW TO TIB FLIES. 



will (if a typical dry fly) rise rapidly, till the tips 

 of its wings touch the surface, when it will 

 remain still, entirely immersed held down by 

 the elastic skin of the water, to which reference 

 has already been made. Before, when the fly 

 was floating properly, it was the elastic skin that 

 held it up. 



It is true, indeed, that this elastic skin of the 

 water is capable of sustaining such a small 

 weight, that, in all ordinary questions of buoyancy, 

 its presence may be altogether ignored, but its 

 influence in dry-fly fishing is supreme. 



A good dry fly, then, should be constructed : 



1. To fall in the correct position. 



2. To fall so gently on the skin of the water as 

 not to break through it. 



3. To distribute its weight so evenly on the 

 skin as to be easily borne up. 



4. To prevent the skin from "creeping" over it. 

 In Chapter V. the last condition has already 



been discussed. We shall now examine some 

 forms of dry flies, and discover how far they fulfil 

 the remaining conditions. 



Forms A, B, and C (Fig. 54) are those most com- 

 monly used, but all have a tendency to fall with the 

 shank of the hook pointing skywards, unless there 

 is just sufficient tension at the end of the gut cast 

 to keep it horizontal. When this is the case, the 

 line of descent being vertical, it follows that the 

 wings should be perpendicular to the shank (as in 

 Form B), if the maximum advantage is to be 

 taken of their parachutic action. Now, while 

 Form A is the truest to nature, Form C is the 

 most evenly balanced when floating in its correct 

 position, and therefore conforms best to the third 

 condition above laid down, so that, on the whole, 

 it would seem that Form B, being a compromise 

 between the two, and having, as has just been 

 demonstrated, a special advantage of its own, is 



