When trout are "bulging" (that is to say, as every angler knows, when they are taking the "nymphæ" just below the surface), it is almost hopeless to endeavour to secure them with a dry, floating fly. The fish are intent on another kind of game, and are best left severely alone.
Unfortunately, even experienced anglers are apt to be deceived by such a fish; the rise is often apparently that of a trout at a surface fly; a little careful observation will, however, convince you that such is not the case, for no floating flies are passing near him at the time of his rise. Don't waste another moment upon him, but try to find another in a more reasonable frame of mind. If all the fish on your stretch of water seem to be similarly occupied, and you are not willing to wait until they have decided to make a change of diet, then a gold ribbed hare's ear may, if fished wet, entice an odd fish, as it somewhat resembles a nympha.
It is, however, very chance work, as is that of endeavouring to secure a "tailing" fish with a down stream fly sunk below the surface, and jerked about in front of where his nose should be. No keen angler would call this serious fishing--it is a mere travesty of the real sport; but it may serve to pass the time, and perchance to wile a trout into your basket. The angler's patience will, however, be far more severely tried when fish are "smutting." What prophet is there who can tell us what we should do then? Those abominable "curses," so well named, appear to be able to baffle entirely the skill of the ablest of our entomologists, and the ability of our most capable of fly dressers. No lure has yet been discovered that can have any reasonable hope of imitating them. To watch a big trout slowly and majestically sail here and there on a still, hot day, barely dimpling the surface as he sucks down one after another of these little insignificant "curses," is quite enough to satisfy you as to the remoteness of your chance of deceiving him. Nothing that human hands could tie could simulate them. Place in the track of one of these fish the smallest gnat in your box, attached to the finest of undrawn gut, delivered with the lightest and truest cast of which the human hand is capable and, as you watch the fish fade slowly down into the depths in disgust at the evident deception, you will realise the hopelessness of your endeavour.