THE FRESH-WATER LOCHS OF SCOTLAND. 
95 
Garry between Struan and Blair Atholl. It contains fine trout, but the 
fishing is strictly preserved. It is surrounded by low, heather-clad hills, 
which slope gradually up from the shores of the loch. There are few 
weeds, and the bottom is sandy, or (in parts) gravelly. Loch Bhac 
trends in a north-east and south-west direction, and is extremely simple 
in outline and in conformation. It is over one-third of a mile in 
length, and one-sixth of a mile in maximum breadth, the mean breadth 
being over one-eighth of a mile, or 33 per cent, of the length. Its 
waters cover an area of about 31 acres, or one-twentieth of a square 
mile, and it drains an area thirty-six times greater, or nearly 2 square 
miles. About 30 soundings were taken, the maximum depth observed 
being 42 feet. The volume of water contained in the loch is estimated 
at 22,104,000 cubic feet, and the mean depth at 16J feet, or 39 per cent, 
of the maximum depth. The length of the loch is 48 times the maximum 
depth, and 122 times the mean depth. Loch Bhac forms a simple basin, 
the bottom sloping gradually down on all sides to the deepest part, 
which is approximately centrally placed, but rather nearer to the 
southern end and to the eastern shore, where the slope of the bottom is 
steeper than at the northern end and off the western shore. The area 
of the lake-floor covered by less than 10 feet of water is about 16 acres, 
or 51 per cent, of the entire area of the loch; that covered by water 
between 10 and 25 feet in depth is about 8 acres, or 25 per cent. ; and 
that covered by more than 25 feet of water is about 7 acres, or 24 per 
cent, of the total area of the loch. Loch Bhac was surveyed on July 6, 
1903, but the elevation of its surface above the sea could not be deter- 
mined from bench-mark, though from a spot-level at the north end of 
the loch it is apparently slightly under 1070 feet. The water rises and 
falls very little, the range being probably less than 1 foot. On com- 
mencing the survey at 6.15 p.m., the temperature of the surface water 
was 53°'0 Fahr., and in the centre of the loch a little later readings at 
the surface, at 25 feet, and at 40 feet gave identical results, 45°*0. 
Loch Con (see Plate XXVIII.). — Loch Con (Chon, or Choin) lies 
to the east of Loch Garry, and flows by the Allt Choin into Erochy 
water, which joins the river Garry at Struan. It was formerly a good 
trout loch, but now contains many pike, which are supposed to have 
been maliciously introduced. Its gradually sloping shores are heather- 
clad, with few large boulders. There are trees on the islands and on the 
promontory at the west end. The outflowing burn goes through a large 
flat mass of moraine debris, which extends far down the burn. The loch 
trends in an east and west direction, and is extremely irregular in 
outline, being almost divided into two portions by a narrow constriction 
near the middle. It is nearly a mile in length, and over a quarter of 
a mile in maximum breadth, the mean breadth being over one-tenth of 
a mile, or 11| per cent, of the length. Its waters cover an area of about 
