Depth and Temperature of Green Lake. 
217 
August, 1890. 
Depth. 
Surface tern. 
Bottom tern. 
17 meters. 
d 
o 
& 
10.25° C. 
24.5 
25. 
7.7 
31. 
26. 
7.45 
33. 
24. 
7.2 
36. 
25.5 
7.2 
40.5 
26. 
7. 
40.85 
25. 
7. 
41.5 
24. 
7. 
42. 
24.5 
rr 
t . 
42.2 
24. 
7. 
43. 
24. 
7. 
45.25 
6.6 
46.75 
24. 
6.6 
48.45 
22. 
6.6 
July, 1891. 
Depth. 
Air tern. 
Surface tern. 
Bottom tern. 
41.85 meters. 
22°.77 C. 
21.° C. 
5.4° C. 
43.5 
23.33 
23. 
5.56 
50. 
22.22 
22. 
5.28 
50.5 
25. 
22. 
5.28 
51.2 
20.55 
22. 
5.28 
56. 
21.11 
21. 
5.28 
57.75 
24.72 
21. 
5.28 
58. 
26.3 
5.28 
We notice that in August, 1890, there was a uniform temperature of 
6.6° C. below a depth of 45 meters, and that up to 25 meters there was 
an elevation of temperature of only one degree. In July, 1891, the bot¬ 
tom temperature was 5.28° C. While we cannot compare temperatures 
taken in August, 1890, with those taken in July, 1891, I think we may 
fairly infer that the maximum bottom temperature in Green Lake is 
reached in August, and that it remains nearly the same during Septeim 
ber and October. The surface temperature is nearly the same in all the 
deeper parts of the lake. Swimmers, in crossing the lake, claim that 
they pass through “streaks” of different temperatures, but the ther¬ 
mometer determinations show a practical uniformity of surface tem¬ 
perature. 
In comparing these temperatures with those obtained by Prof, and 
Mrs. Peckham in Pine Lake (Trans. Wis. Acad. V, 273), I notice that 
