THE FRESH-WATER LOCHS OF SCOTLAND. 
225 
The temperature was found to be constant from the surface to a 
depth of 15 feet, thence the temperature fell 4° to the bottom in 40 
feet. 
Loch Tollie (see Plate XL VII.). — Loch Tollie is situated miles to 
the west of the lower end of Loch Maree, and drains into its north- 
western arm. The ground immediately surrounding the loch is low, 
though Meall Airidh Mhic Criadh to the south-west, and Creag Mhor 
Thollie to the south-east, rise to over 1100 feet. The loch is roughly 
elliptical in outline, the major axis having an east and west direction. 
One of the islands near the northern shore was for some time a strong- 
hold of the McLeods. 
Loch Tollie was surveyed on July 29, 1902, the elevation of the lake- 
surface being 387*0 feet above sea-level ; when visited by the Ordnance 
Survey officers on November 13, 1869, the level was found to be 387*7 
feet. The water must at one time have stood at a higher level, for at 
the east end, where the stream leaves the loch, there are the remains of 
a dam (now fast disappearing), which held up the water for supplying 
a mill farther down the burn. 
Loch Tollie is under a mile in length, with a maximum breadth of 
about 800 yards, the mean breadth being about 500 yards. Its waters 
cover an area of about 169 acres (a quarter of a square mile), and it 
drains an area eight times greater, or 2 square miles. The maximum 
depth of 86 feet was observed in the centre of the loch off the mouth 
of the Allt Loch Laraig. The volume of water is estimated at 244 
millions of cubic feet, and the mean depth at 33 feet. The breadth of 
the loch at the position of the deepest sounding is 27 times the depth. 
The shore development is small (1*11), and the insulosity 0*002. The 
deeper water occurs in the western part of the loch, though the 25-feet 
area sends a narrow tongue into the eastern part. The 75-feet area 
in the centre of the loch is small, with a narrow tongue extend- 
ing towards the northern shore. The areas between the consecutive 
contour-lines, and the percentages to the total area of the loch, are 
as follows : — 
0 to 25 feet 
81 acres 
48*0 per 
cent. 
25 „ 50 „ 
43 „ 
•25*6 
5 J 
50,, 75 ,, 
35 „ 
20-6 
? > 
Over 75 ,, 
10 ,, 
5-8 
- 
169 ,, 
100*0 
) > 
Temperature Observations . — 
-The following 
series of 
temperatures 
s taken in the centre of 
the loch at 
6 p.m. 
on July 29, 
1902: — 
Q 
