PHYS.—You just now said, that a fish pricked by the hook of an artificial fly would not usually take it again that season. HAL.—I cannot be exact on that point: I have known a fish that I have pricked retain his station in the river, and refuse the artificial fly, day after day, for weeks together; but his memory may have been kept awake by this practice, and the recollection seems local and associated with surrounding objects; and if a pricked trout is chased into another pool, he will, I believe, soon again take the artificial fly. Or if the objects around him are changed, as in Autumn, by the decay of weeds, or by their being cut, the same thing happens; and a flood, or a rough wind, I believe, assists the fly-fisher, not merely by obscuring the vision of the fish, but, in a river much fished, by changing the appearance of their haunts: large trouts almost always occupy particular stations, under, or close to, a large stone or tree; and, probably, most of their recollected sensations are connected with this dwelling. PHYS.—I think I understand you, that the memory of the danger and pain does not last long, unless there is a permanent sensation with which it can remain associated,—such as the station of the trout; and that the recollection of the mere form of the artificial fly, without this association, is evanescent. ORN.—You are diving into metaphysics; yet I think, in fowling, I have observed that the memory of birds is local. A woodcock, that has been much shot at and scared in a particular wood, runs to the side where he has usually escaped, the moment he hears the dogs; but if driven into a new wood, he seems to lose his acquired habits of caution, and becomes stupid. POIET.—This great fish, that Ornither has just caught, must be nearly of the weight I assigned to him. HAL.—O no! he is, I think, above 5lbs., but not 6lbs.; but we can form a more correct opinion by measuring him, which I can easily do, the but of my rod being a measure. He measures, from nose to fork, a very little less than twenty-four inches, and, consequently, upon the scale which is appropriate to well-fed trouts, should weigh 5lbs. 10oz.—which, within an ounce, I doubt not, is his weight. PHYS.—O! I see you take the mathematical law, that similar solids are to each other in the triplicate ratio of one of their dimensions. HAL.—You are right. PHYS.—But I think you are below the mark, for this appears to me an extraordinarily thick fish. HAL.—He is a well-fed fish, but, in proportion, not so thick as my model, which was a fish of 17 inches by 9 inches, and weighed 2lbs.; this is my standard solid. We will try him. Ho! Mrs. B.!—bring your scales, and weigh this fish. There, you see, he weighs 5lbs. 10½oz. PHYS.—Well, I am pleased to see this fish, and amused with your sport; but though I have been imitating you in throwing the fly, as well as I can, yet not a trout has taken notice of my fly, and they seem scared by my appearance.