16 
Appendices to Tenth Annual Report 
Obstructions Shortly after reaching Loch Torridon I proceeded to inspect the 
on Amhain Amhain Thrail, the principal tributary of the Torridon, which tiows out 
Thrail. 0 f a moun tain lake nearly a square mile in extent, and after a course of 
about 3 miles joins the Torridon near its mouth. There are several 
natural obstructions in the course of this stream, and Lord Lovelace, to 
whom it belongs, and who is proprietor of the estate of Ben Damph on 
the south shore of Loch Torridon, is anxious to make these obstructions 
passable, so as to allow of the ascent of salmon into the loch from which 
it flows. I accordingly carefully inspected the whole course of the stream, 
in company with the head keeper at Ben Damph, from its junction with 
the Torridon up to its parent loch. 
Near the junction of the Thraill with the Torridon, the water at the 
mouth of the former was rather dead and still when I visited it, whereas 
there was a strong stream in the Torridon. It would, I think, be advisable 
to narrow the mouth of the Thraill in order to increase the rapidity of the 
current, as a brisk stream is more attractive to salmon than still water. 
The Thraill has a course about 3 miles from Loch Nam Fiad to its 
junction with the Torridon. The loch is 586 feet above the level of the 
sea, so that the river has a fall of nearly 200 feet per mile ; and the effect 
of this precipitous descent is that it runs out very soon after a flood, and 
remains in good angling condition for but a short period. 
I am inclined to think that it would greatly improve the angling in the 
Thraill if an artificial loch were formed not far from its junction with the 
Torridon, at a point where there are two large boulders just beneath the 
lower end of a small island in the stream. Here a dam of stones or con- 
crete might be constructed across the river, so as to form a small loch, 
probably about 7 or 8 acres in extent, which would serve as a lie for salmon 
and sea trout. This might be done without incurring much expense. 
But it would certainly cost a very considerable sum to open up the falls 
and rapids which intervene between the mouth of the Thraill and Loch 
Nam Fiad ; and it seems to me very doubtful whether the result, in the 
shape of improved angling, would be such as to repay the outlay. 
The first natural obstruction which entirely prevents the ascent of 
salmon is a long rapid, somewhat less than a mile above the mouth of the 
river. At present there are several straggling and disconnected streams 
pouring over the face of the rock. These should be united and concen- 
trated on the left bank, and several resting pools should be formed, in 
order to enable fish to rest and recruit in the course of the long ascent 
they have to make. The Ben Damph keeper, who accompanied me 
during my inspection, is quite able to explain my views of what ought 
to be done in the event of its being decided to attempt to make this rapid 
passable for salmon. 
About a third of a mile above this rapid there is a water-fall, which is 
a very formidable obstruction. It is at least 18 feet high, with perpen- 
dicular walls of rock on each side of the chasm below the fall. There is 
a long, deep, dark pool beneath the fall, which would likely be a favourite 
lie for salmon if they were enabled to reach it. It would, however, cost 
a large sum to make this fall passable. A plan has more than once oc- 
curred to me when examining such falls as this, where there is a lofty and 
totally impassable obstruction, with perpendicular walls of rock hemming in 
the chasm on each side of the pool below the fall. It is as follows : — 
Construct a ^\^J~ shaped wooden shoot, extending from the water above 
the fall along one of the perpendicular walls of rock to the pool 
below. This should be supported on iron struts fixed in the rock ; and 
the gradient should not be steeper than 1 in 10 or 11. The flatter the 
