208 |Wisconsin Academy of Sciences, Arts, and Letters. 
higher than those recorded. It is possible that this is also due to 
lack of sunshine. In any case, it seems plain that the large 
budgets of loch Ness are exceptional among the Scottish lakes 
in much the same way that those of lake Geneva are among those 
of the Swiss lakes. 
The figures given by Halbfass (’10, p. 61) would assign a 
budget to loch Ness for 1904 amounting to 43,000 cal. This is 
somewhat higher than my computation shows, but is a wholly 
possible budget and one that loch Ness has doubtless reached. 
No. 30. Loch Katrine.—Halbfass (’05, p. 226-227) gives the 
temperature of loch Katrine on Mar. 10, 1900 as 5.52°; Sept. 6, 
1900, 11.16°. These figures he repeats (TO, p. 62). If, how¬ 
ever, the mean temperature of the water is derived from table 
1 of his pvper of 1910, by dividing the total heat by the volume 
of the lake, the temperature for Mar. 10 would be 4.42°; Sept. 
6, 8.91°. I have computed mean temperatures for loch Katrine, 
basing my results for volume on the areas given by Murray; and 
my result for Sept. 9, 1812 is 8.00°, the same as that of Halbfass 
(’05, p. 227) ; so that my hydrographic data seem to be the same 
as his. The temperature records which I have used for comput¬ 
ing the temperatures of 1900 come from Forel (’01, p. 37) and I 
cannot see that my results are in error. In the temperature rec¬ 
ords, no reading is given at 25 m., and the temperature depends 
somewhat on the reading inserted there, but the mean tempera¬ 
ture could not go above 8.8° in any case. The mean depth of the 
lake as given by Murray (Yol. II, p. 3) is 199 ft. which equals 
61 m., not 62 m. as stated by Halbfass. If the temperature de¬ 
rived from table 1 in Halbfass’ paper of 1910 are employed, the 
heat budget would be 27,400 cal., substantially the same as mine. 
No. 31. Wettern.—The annual heat budgets of this lake are 
by no means extraordinarily large. The wind-distributed heat 
is small, owing evidently to the low temperature of the water in 
winter and the relatively late date at which the lake reaches the 
temperature of 4°. This lake lends no support to Forel’s doc¬ 
trine of increasing budgets with increasing latitude. The com¬ 
ment on Fig. 1 (p. 21) should be consulted for a discussion of 
the low summer heat-income of this lake and the next two. 
No. 32. Mjosen.—The average heat budget of this lake is large, 
though if the budget for 1901 be omitted it is smaller than that 
of loch Ness. There is no question but that the temperatures 
of the lake for 1901 are correctly recorded and computed but it 
