Such are the only specimens which our limits enable us to present to the reader; but we hope they will be sufficient to induce him to turn to the work itself--and we doubt not--for his further gratification. Digressions occur too frequently to suit the pioneering taste of a certain class of readers; they may serve as resting-places in an intricate plot, but they were not, on that account, wanted here. At the same time, they are recommended by plain sense, knowledge of the world, shrewdness, and harmless satire on the weak sides of our nature, and are therefore _useful_; whilst their terseness and vivacity will free them from the charge of dulness, or the sin of prosing. * * * * * DIALOGUES ON FLY FISHING. _By Sir Humphry Davy._ We continue our extracts from this "philosophical angler's" delightful little book. The present will serve such as are unacquainted with the mysteries of fly-fishing, and interest all who are fond of inquiries in natural history. _Management of Flies._ _Hal_--Whilst you are preparing I will mention a circumstance which every accomplished fly-fisher ought to know. You changed your flies on Saturday with the change of weather, putting the dark flies on for the bright gleams of the sun, and the gaudy flies when the dark clouds appeared. Now I will tell you of another principle which it is as necessary to know as the change of flies for change of weather; I allude to the different kinds of fly to be used in particular pools, and even for particular parts of pools. You have fished in this deep pool; and if you were to change it for a shallower one, such as that above, it would be proper to use smaller flies of the same colour; and in a pool still deeper, larger flies; likewise in the rough rapid at the top, a larger fly may be used than below at the tail of the water; and in the Tweed, or Tay, I have often changed my fly thrice in the same pool, and sometimes with success--using three different flies for the top, middle, and bottom. I remember when I first saw Lord Somerville adopt this fashion, I thought there was fancy in it; but experience soon proved to me how accomplished a salmon-fisher was my excellent and lamented friend, and I adopted the lesson he taught me, and with good results, in all bright waters. _Hooks._