For ordinary work select a double-tapered line, both ends graduated, of thirty yards' length. The length of the taper varies from fifteen (occasionally less) to eighteen feet. As to the proper length of taper, that again, other things being equal, depends somewhat upon the nature of the fishing for which the line will be used. If rather short casts are to be a rule, a short taper will work best for the reason that more of the "swell" of the line will be in use and not merely wound upon the reel. A short taper also works best against the wind for the same reason.
It should be obvious, although the fact has not been adequately emphasized by angling writers, that if the caster can as a rule (owing to the restricted nature of the stream, which may be small and with banks thickly wooded) use only the light tapered end of his line on a rod really adapted to the size of the swell of the line, he is working at a great disadvantage. For average small-stream fly casting it is best to select a line having a "quick" taper, fifteen feet or less.
The leaders furnished by the tackle dealers especially for dry-fly fishing are usually of very good quality--the best is none too good--with dropper loops, of course, and from six to nine feet in length. The angler who elects to tie his own leaders, a very simple matter and by far the better plan, should purchase the very best silk-worm gut for the purpose--round, hard and clear. It will be necessary to have gut of different weights or caliber from heavy to very fine, in order that the leader may be tapered from about the size of the end of the reel line to very fine undrawn gut nearest the fly. Drawn gut was at one time extensively used by dry-fly fishermen, but it is now generally recognized that fine undrawn gut is quite as efficient and the additional strength gained by its use is a distinct advantage.
The tapered leader certainly aids materially in fine work over clear, still water and shy fish. I believe it was Henry P. Wells, the author of "Fly-Rods and Fly Tackle," a work familiar to both American and English fly fishermen, who stated that in his opinion the most important factor for successful fly fishing was to make invisible any connection between the fly and the line, and the use of fine terminal tackle tends to bring this about. Moreover, fine caliber gut near the fly assists in floating it. Better, straighter casting can be done when a tapered leader is used.