‘ 
Chemistry and Physics. ee 
trum.— Comptes Rendus, Dec. 10, 1883, p. 1384. 1% 
Tahoe, also 
called Lake Bigler, is situated at an altitude of 6247 feet in the 
1495, 1500, 1506, 1540, 1504, 1600, 1640, 1645. This depth ex- 
ceeds that of the Swiss Lakes proper—Lake Geneva, for exam- 
ple, has a maximum depth of 1096 feet—but is considerably less 
than that of Lakes Maggiore and Como on the Italian side of the 
A A series of observations of the temperature of the water 
were taken between the 11th and 18th of August. The average 
corrected results are as follows: : 
Depth in feet. Temp. (C.) Depth in feet. Temp. (C.) 
re (surface) 9°4 _ 330 (bottom) = 
17°2 
100 12°8 480 (bottom) 69 
150 10-0 50 67 
200 “9 600 61 
250 - $3 772 (bottom) 50 
300 78 1506 (bottom) 40 
a temperature, therefore, diminishes with increasing depth to 
2 ut 700 or 800 feet, and below this remains sensibly the same 
“o wa to 1506 feet; or in other words a constant temperature of 
heehee density of water, and it confirms the recent observations 
of frofessor Forel in Switzerland; he found, for example, that a 
fepth of nearly 400 feet, the lake being covered with 
Inches of ice. "The explanation of the observed fact that Lake 
oe does not entirely freeze I i oe ae 
the bottom which does not allow the necessary decomposition to 
