101 
1908-9]. Temperature Observations in Loch Garry. 
Approximate estimates were made of the quantity of heat stored in the 
lake for successive weeks during the period of observation. The method 
employed was to calculate roughly from the contour of the lake basin the 
quantity of water between the surface and a depth of 10 feet, between 
depths of 10 and 25 feet, 25 and 50 feet, and so on. The mean was then 
taken of all observations at the centre of the lake during each week, at the 
surface, 10 feet, 25 feet, 50 feet, etc. ; and, on the assumption that these mean 
values were the means for all parts of the lake, a rough calculation was 
made of the quantity of heat passing into or out of the lake from week to 
week. As the observations from which the means were taken were all 
made about the centre of the lake, it is thought that the assumption that 
they are typical of the whole lake is sufficiently accurate for the present 
purpose. 
Table II. gives the results of these calculations. The positive sign 
denotes that heat entered the lake, the negative sign that there was a loss 
of heat. A separate column gives the mean surface temperature for the 
successive weeks. 
Table II. 
Week 
ending 
Gram 
calories 
Mean 
Surface 
Week 
ending 
Gram 
calories 
Mean 
Surface 
-M0 10 
Temperature. 
+ 10 10 
Temperature. 
Feb. 3 
-3200 
38-3 
Apr. 27 
+ 1200 
41*3 
„ io 
H-4800 
37’8 
May 4 
+ 2800 
41 '5 
M 17 
38-6 
„ 11 
437 
+ 1500 
+ 8000 
„ 24 
-4200 
38-3 
„ 18 
+ 11700 
46-0 
Mar. 2 
-2900 
38-2 
„ 25 
+ 13700 
46*3 
„ 9 
372 
June 1 
55-0 
- 1800 
+ 12800 
„ 16 
+ 2100 
37-0 
„ 8 
+ 4700 
56-0 
„ 23 
+ 2600 
37-7 
„ 15 
- 800 
52-3 
„ 30 
+ 4600 
38T 
„ 22 
+ 6600 
53T 
Apr. 6 
+ 4500 
39-2 
„ 29 
+ 8800 
58-5 
„ 13 
+ 4100 
39-8 
July 6 
+ 200 
66-8 
„ 20 
+ 3800 
40-9 
„ 13 
- 1800 
61-4 
„ 27 
41-3 
„ 20 
59-4 
