In the year 1841, Mr Young marked a few spawned salmon along with his grilse, employing as a distinctive mark copper wire instead of brass.  One of these, weighing twelve pounds, was marked on the 4th of March, and was recaptured on returning from the sea on the 10th of July, weighing eighteen pounds.  But as we know not whether it made its way to the sea immediately after being marked, we cannot accurately infer the rate of increase.  It probably becomes slower every year, after the assumption of the adult state.  Why the salmon of one river should greatly exceed the average weight of those of another into which it flows, is a problem which we cannot solve.  The fact, for example, of the river Shin flowing from a large lake, with a course of only a few miles, into the Oykel, although it accounts for its being an early river, owing to the receptive depth, and consequently higher temperature of its great nursing mother, Loch Shin, in no way, so far at least as we can see, explains the great size of the Shin fish, which are taken in scores of twenty pounds’ weight.  They have little or nothing to do with the loch itself, haunting habitually the brawling stream, and spawning in the shallower fords, at some distance up, but still below the great basin;[22] and there are no physical peculiarities which in any way distinguish the Shin from many other lake born northern rivers, where salmon do not average half the size.

[21] Mr Shaw, for example, states the following various periods as those which he found to elapse between the deposition of the ova and the hatching of the fry—­90, 101, 108, and 131 days.  In the last instance, the average temperature of the river for eight weeks, had not exceeded 33 deg..

[22] If we are rightly informed, salmon were not in the habit of spawning in the rivulets which run into Loch Shin, till under the direction of Lord Francis Egerton some full-grown fish were carried there previous to the breeding season.  These spawned; and their produce, as was to be expected, after descending to the sea, returned in due course, and, making their way through the loch, ascended their native tributaries.

Leaving the country of the Morer Chatt (the Celtic title of the Earls of Sutherland) we shall now return to the retainer of the “bold Buccleuch.”  We have already mentioned that Mr Shaw, having so successfully illustrated the early history of salmon, next turned his attention to a cognate subject, that of the sea-trout (Salmo-trutta?) Although no positive observations of any value, anterior to those now before us, had been made upon this species, it is obvious that as soon as his discoveries regarding salmon fry had afforded, as it were, the key to this portion of nature’s secrets, it was easy for any one to infer that the old notions regarding the former fish were equally erroneous.  Various modifications of these views took place accordingly; but no one