92 
BATHYMETRICAL SURVEY OF 
Allt na Breaclaich. It trends in a north and south direction, and is 
extremely simple in outline and conformation; it is oblong in outline, 
and of nearly uniform width throughout. It is nearly three-quarters 
of a mile in length, and over one-eighth of a mile in maximum breadth, 
the mean breadth being one-tenth of a mile, or 14 per cent, of the 
length. Its waters cover an area of about 47 J acres, and it drains an 
area 16 times greater, or about IJ square miles. Over 40 soundings 
were taken, the maximum depth observed being 39 feet. The volume of 
water is estimated at 22,682,000 cubic feet, and the mean depth at 11 
feet, or 28 per cent, of the maximum depth. The length of the loch is 
99 times the maximum depth, and 350 times the mean depth. The 
northern portion of the loch is shallow, and water deepening gradually 
on proceeding southwards until the maximum depth is encountered 
about one-eighth of a mile from the southern end, thence the water 
shallows rapidly towards the south end. The 10-feet basin is about half 
a mile in length, extending from near the south end to within one-sixth 
of a mile from the north end. The 2 5 -feet basin is contained in the 
southern half of the loch, and is about a quarter of a mile in length. 
The area of the lake-floor covered by less than 10 feet of water is over 
29 acres, or 62 per cent, of the entire area of the loch, while that covered 
by more than 10 feet of water is over 18 acres, or 38 per cent., of which 
8 per cent, exceeds 25 feet in depth. Lochan na Lairige was surveyed 
on June 16, 1903; the surface of the water was estimated at about 1595 
feet above the level of the sea. 
Lochs Daimh and Giorra . — Lochs Dainih and Giorra, situated in the 
wilds of Glenlyon, amid grand and mountainous scenery, are good 
trouting lochs, but strictly preserved. Loch Daimh flows into Loch 
Giorra by a short river, and the outflow from both lochs is carried into 
the river Lyon by the Allt Conait. To the south, on the flanks of 
Stuchd an Lochain, lies the small Lochan nan Cat, at an elevation of 
over 2000 feet above the sea, which flows into the river between Lochs 
Daimh and Giorra. It being reported that this little lochan was frozen 
over a few days before the date of the survey of Lochs Daimh and 
Giorra, it was visited in the hope of taking soundings through holes in 
the ice, but the ice had disappeared. It was apparently shallow all 
round the shore, except where there are screes from the cliffs, and, .if 
at all deep, it must be over a very limited area. The temperature of 
the water was 53°-0 Fahr., while a reading taken close under the crags 
beside the snow gave 49°-8. 
Loch Daimh (see Plate XXVII.). — Loch Daimh (or Damh) trends 
in an east-and-west direction, being widest and deepest towards the west 
end, narrowing and shallowing towards the east end. It is nearly a 
mile in length, and nearly one-third of a mile in maximum breadth, 
the mean breadth being nearly one-fifth of a mile, or 19 per cent, of 
