THE FRESH-WATER LOCHS OF SCOTLAND. 
399 
contents amount to 62 millions of cubic feet. The drainage area, which 
includes Loch an Staca, is 4 square miles. Beyond the burn from Loch 
an Staca, and another from the hill (2222 feet) on the west, it receives 
only superficial drainage. The burn Allt Bhlair flows out to the south- 
east, and, joining that from Loch na Criche, enters the river Moriston. 
The basin is quite simple, the deeper water nearer the south-east side, 
and the maximum depth of 55 feet towards the north-east end. 
When surveyed on June 10, 1904, the level was found to be 1494T 
feet above the sea, which differs little from the level determined by the 
Ordnance Survey officers on May 15, 1869, viz. 1494*4 feet. 
The surface temperature was 56°*9 Fahr. 
L(Tch nam Breac Dearga (see Plate XCI.). — Situated on the high 
ground to the west of Loch Ness, about IJ miles distant from the middle 
part of that loch. It lies close to the west of Meall Fuarvounie (2284 
feet high), which separates it from Loch Ness. The loch is elongate, 
lying nearly north-east and south-west, and of irregular form, roughly 
oblong. The surrounding moorland rises little above the loch, except 
on the east, where the crags of Meall Fuarvounie rise close beside the 
loch. 
This loch was locally reputed to be of great depth, or even supposed 
to be bottomless. Though we found it to be the deepest loch in this 
elevated tract between Glen Urquhart and Glen Moriston, its depth was 
not remarkable, and not greatly in excess of that of Lochs Liath and an 
Staca in the same district. It is three-quarters of a mile in length, 
about one-fifth of a mile in greatest breadth, and one-eighth of a mile 
in mean breadth. 
The superficial area is about 56 acres, and drains about two-thirds 
of a square mile. It contains 60 million cubic feet of water. It is 
drained by a burn running some 2 miles south-westward, into the Allt 
nan Saighead (Alltsigh), which also receives the overflow of a host of 
little lochs, which were not surveyed, and runs into Loch Ness. The 
height above the sea was estimated at 1570 feet. 
The basin is simple, but deepest toward the upper or north end. 
The lower portion is all under 25 feet in depth. The areas of over 
25 feet and over 50 feet pass obliquely across the loch from south to 
north. The 50-feet contour encloses a narrow area, about a quarter 
of a mile long, with the deepest sounding, 70 feet, in the middle of 
the loch, but nearer the north end. 
The surface temperature on June 1, 1904, was 52°*9 Fahr. ; at 10 
feet, 52°*7 ; at 25 feet, 48°*2 ; and at 60 feet, 46°*2, giving a total range 
of 6°*7, the greatest fall being one of 4°*5 between 10 and 25 feet. 
Loch a! Yulian (see Plate Cl.). — A little loch of triangular form, 
in the elevated hilly country to the west of Loch Ness, and about 
