or level; for American rods weighing 43/4 to 51/4 ounces, size E, tapered or level; for American rods weighing 51/2 to 6 ounces, size D tapered, size E level; for American rods weighing 6 ounces or more, size C, tapered or level.
Much, of course, depends on the action of the rod. A stiff rod requires a heavier line than a limber one and a British rod having considerable weight in the butt can handle a smaller line than an American rod of the same ounces.
English makers use numbers to designate the sizes of their lines. One well-known make corresponds with American sizes as follows:
Strength
The enameled line is made very heavy compared with the soft light line used in bait casting. Bait casters judge their lines by their test in pounds and it is for the benefit of the bait caster taking up fly fishing that I bring up this subject. No ordinary fly rod can lift three pounds and experiments show that a fish pulls approximately its own weight — and a standard Size E fly line tests around 25 pounds! It is a good plan to snip off an inch or so of line from time to time. Failure to do so has often resulted in a lost fish.