HAL.—However full a river may be of trout and grayling, there is a certain limit to the sport of the angler, if continuous fishing be adopted in the same pools. Every fish is in its turn made acquainted by diurnal habit with the artificial fly, and either taken or rendered cautious; so that, in a river fished much by one or two good anglers, many fish cannot be caught, except under peculiar circumstances of very windy, rainy, or cloudy weather, when many flies come on; or at night, or at the time the water is slightly coloured by a flood, or when fish change their haunts in consequence of a great inundation. In the Usk, in Monmouthshire, when it was very full of fish in the best fishing time, when the spring brown and dun flies were on the water, it was not usual for some excellent anglers, who composed a party of nine, and who fished in this river for ten continuous days, to catch more than two or three fish each person. But one day, when the water was coloured by a flood, in which case the artificial fly could not be distinguished by the fish from the natural fly, I caught twelve or fourteen of the same fish, that had been in the habit of refusing my flies for many days successively. This was in the end of March, 1809, when the flies always came on the water with great regularity; the blues in dark days, the browns in bright days, between twelve and two o’clock in the middle of the day. In rivers where the artificial fly has never been used, I believe all the fish will mistake good imitations for natural flies, and in their turn, to use an angler’s phrase, “taste the steel;” but even very imperfect imitations and coarse tackle, which are only successful at night or in turbid water, are sufficient to render fish cautious. This I am convinced of, by observing the difference of the habits of fish in strictly preserved streams, and in streams where even peasants have fished with the coarsest tackle. I might quote the Traun at Ischl, where the native fisherman used three or four of the coarsest flies on the coarsest hair links made of four or five or six hairs, and the Traun at Gmunden, where they are not allowed to fish. The fish that rose took with much more certainty at Gmunden than at Ischl. At a time when many flies are on, particularly large ones, a few days of continuous fishing, even with a single rod, will soon make the sport indifferent in the best rivers; but the larger and the deeper the river the longer it continues, because fish change their stations occasionally, and pricked fish sometimes leave their haunts, which are occupied by others; and graylings are more disposed to change their places than trouts.