Dr. B. F, Harrison on Solution of Ice on Inland Waters. 51 
time was 2°17 inches, which included the water obtained by 
melting snow, which fell to the depth of 10 inches. 
he mean temperature of the atmosphere from Jan. 28 to Feb. 
15 was 26°4. ‘The fall of water for this period was 1°36 inches, 
including six inches of snow. The observations of Feb. 23d 
were made with great difficulty, as the temperature of the at- 
mosphere was only 18° F., and the water on the thermometer 
when brought to the surface was quickly converted into ice so 
that it was difficult to keep it cl 
rapidly disappearing: one-fourth or one-third of the ice which 
I found on the lake disappeared during two hours while I re- 
mained in sight of the lake. With the aid of a boat I found 
the temperature of the lake, in the middle of the open water, to 
be 42° from the surface to the bottom, Near the edge of the 
remaining field of ice the temperature was 41° from the surfice 
to the bottom. Close to the edge of the ice the temperature 
varied from 34° to 88°. The mean temperature of the lake at 
this time may be considered about 41°5 F. 
July 11th, 1860, I found the temperature of the lake at the 
surface '73°°5. Aug. 18th, 1860, the temperature of the surface 
of shallow water near the shore was 77 °; near the centre of the 
lake the surface water was 75° ; at adepth of 15 feet, 74°; at the 
bottom (24 feet), 78°. 
pt. 15th, 1860 (at 54 P. m.), surface water 67° to 68° with 
ed perceptible difference from the surface to the bottom. 
ct. 27th, 1860. Clear and warm all day—no wind. 
servations were made at 4 P. M. Temperature of the surface of © 
the lake 54°'5; 6 ft. below the surface 53°; at 12 ft., 53°; at 18 
ft, 52°-5; at 24 ft., 52°-5, | 
Dec. 6th, 1860. There was no ice on the lake and the tem- 
Perature was 42°-5 from the surface to the bottom, 226 
— 17th, 1860. The lake was covered with ice 6 in. thick. 
*mperature of the surface under the ice, 34°. 
Atad : ‘ at 12 ft. 354°. : 
one pth * rae « 94 ft, (bottom) 363°, 
The mean of the whole is 35°-4; but it is probable that the ob- 
servation at the surface was affected by the agitation of the water 
wa cutting the ice ;~-if we put the temperature of the surface at 
824° the mean will be 85°°1. ‘The temperature of the air at 2 
P.M. was 35° 
2 on 5th, 1861, the ice was 10 inches thick. Temperature of 
water immediately under the ice 824°. 
