of Edinburgh , Session 1885 - 86 . 
419 
Table VIII . — Collected Observations in Luss Basin , 1885. 
Date, 
Sept. 5. 
Sept. 22. 
Oct. 15. 
Nov. 14. 
Depth. 
Temperature (Fahr.). 
o 
O 
0 
o 
0 
56-2 
53-6 
49-4 
46°6 
5 
55-9 
53-5 
49*2 
10 
55*75 
53-45 
49-05 
46-3 
15 
49 T 
53*4 
49-0 
20 
48-3 
48 -8 
49T 
46-3 
30 
47-0 
47-55 
48-9 
46-3 
Taking the depth at the Ross Mill station as 35 fathoms, we have 
the following values for the mean temperature of the whole of the 
water : — 
Date, . . 5th Sept. 22nd Sept. 15th Oct. 14th Nov. 
Mean temperature, 50°*71 50°'71 49 o, 03 46°’3 
The mean temperatures on the 5th and 22nd September are 
identical, hence the epoch of maximum heat in the water must fall 
between these two dates, and as cooling goes on more rapidly than 
heating, it will fall nearer the 22nd than the 5th, and may with 
safety he said to occur in the third week of September. The curves 
of the 5th and 22nd September intersect at a depth of 13 5 
fathoms, hence the temperature at 13*5 fathoms was the same on 
both these dates. But on the earlier one the temperature of the 
water at that depth was rising, whereas at the later one it is falling, 
therefore it must have attained a maximum some time between 
these dates, and no doubt in the third week of September. The 
curves of 22nd September and 15th October intersect at 1 9*5 
fathoms; here the temperature of the water at both dates was 
49° *0. The maximum temperature in this layer must have been 
attained towards the end of the first week of October. Similarly, 
from the intersection of the curves of 5th September and 15th 
October, we should infer that the maximum temperature at 16 
fathoms occurs in the last days of September. It is probable that 
temperature at the bottom (35 fathoms) was about its maximum on 
15th October. 
