Birge—An Unregarded Factor in Lake Temperatures. 991 
I. 
II. 
III. 
IV. 
V. 
VI. 
Liters 
Temp. 
Density. 
Difference. 
Rel. Dif. 
Ergs. 
for 1 kg. 
for 1°. 
Auftrieb. 
0 
0.999868 
+ 0.000059 
7.38 
0.0491 
17000 
1 
0.999927 
+ 0.000041 
5.12 
0.0342 
24400 
2 
0.999968 
+ 0.000024 
3.00 
0.0200 
41700 
3 
0.999992 
+ 0.000008 
1.00 
0.0067 
125000 
4 
1.000000 
— 0.000008 
1.00 
0.0067 
125000 
5 
0.999992 
— 0.000024 
3.00 
0.0200 
41700 
6 
0.999968 
— 0.000039 
4.88 
0.0325 
25600 
7 
0.999929 
— 0.000053 
6.62 
0.0441 
18900 
8 
0.999876 
— 0.000068 
8.50 
0.0566 
14700 
9 
0.999808 
— 0.000081 
10.12 
0.0675 
12400 
10 
0.999727 
— 0.000095 
11.88 
0.0791 
10500 
11 
0.999632 
— 0.000107 
13.38 
0.0891 
9300 
12 
0.999525 
—0.000121 
15.12 
0.1008 
8300 
13 
0.999404 
- r - 0.000133 
16.62 
0.1108 
7500 
14 
0.999271 
— 0.000145 
18.12 
0.1208 
6900 
15 
0.999126 
— 0.000156 
19 . F 0 
0.1299 
6400 
16 
0.998970 
— 0.000169 
21.12 
0.1408 
5900 
ir 
0.998801 
— 0.000179 
22.38 
9.1491 
5600 
18 
0.998622 
— 0.000190 
23.75 
0.1583 
5300 
19 
0.998432 
—0.000202 
25.25 
0.1683 
5000 
20 
0.998230 
—0.000211 
26.38 
0.1758 
4700 
21 
0.998019 
—0.000222 
27.75 
0.1849 
4500 
22 
0.997797 
— 0.000232 
29.00 
0.1993 
4300 
23 
0.997565 
— 0.000242 
30.25 
0.2016 
4100 
24 
0.997323 
— 0.000252 
31.50 
0.2099 
4000 
25 
0.997071 
— 0.000261 
32.62 
0.2174 
3800 
26 
0.996810 
— 0.000271 
33.88 
0.2257 
3700 
27 
0.996539 
— 0.000280 
35.00 
0.2332 
3600 
28 
0.996259 
— 0.000288 
36.00 
0.2399 
3500 
29 
0.995971 
— 0.000298 
37.25 
0.2482 
3400 
30 
0.995673 
Column III shows the differences between the successive 
numbers of column II and indicates the change in density 
caused by a temperature change of 1°. The significant figures 
also show the difference in weight, in milligrams, between a 
