informed by a Sutherland
correspondent of a fact of another nature, which bears strongly upon the
pertinacity with which these fine fish endeavour to regain their
spawning ground. By the side of the river Helmsdale there was once a
portion of an old channel forming an angular bend with the actual river.
In summer, it was only partially filled by a detached or landlocked
pool, but in winter, a more lively communication was renewed by the
superabounding waters. This old channel was, however, not only resorted
to by salmon as a piece of spawning ground during the colder season of
the year, but was sought for again instinctively in summer during their
upward migration, when there was no water running through it. The fish
being, of course, unable to attain their object, have been seen, after
various aerial boundings, to fall, in the course of their exertions,
upon the dry gravel bank between the river and the pool of water, where
they were picked up by the considerate natives.

No sooner had Mr Young satisfied himself that the produce of a river
invariably returned to that river after descending to the sea, than he
commenced his operations upon the smolts--taking up the subject where it
was unavoidably left off by Mr Shaw[17]. His long-continued
superintendence of the Duke of Sutherland's fisheries in the north of
Scotland, and his peculiar position as residing almost within a few
yards of the noted river Shin, afforded advantages of which he was not
slow to make assiduous use. He has now performed numerous and varied
experiments, and finds that, notwithstanding the slow growth of parr in
fresh water, "such is the influence of the sea as a more enlarged and
salubrious sphere of life, that the very smolts which descend into it
from the rivers in spring, ascend into the fresh waters in the course of
the immediate summer as grilse, varying in size in proportion to the
length of their stay in salt water."

[17] Mr Young has, however, likewise repeated and confirmed Mr
Shaw's earlier experiments regarding the slow growth of salmon
fry in fresh water, and the conversion of parr into smolts. We
may add, that Sir William Jardine, a distinguished
Ichthyologist and experienced angler, has also corroborated Mr
Shaw's observations.

For example, in the spring of 1837, Mr Young marked a great quantity of
descending smolts, by making a perforation in their caudal fins with a
small pair of nipping-irons construct