cm. It was as bright and transparent as glass and entirely without air-bubbles. To walk on it was like walking on a glittering sheet of water; we saw the dark-backed fish darting in and out amongst the Algae underneath our feet. By noon on the following day the thickness of the ice at the two points mentioned had increased to
II.8 and 7.6 cm. respectively.
On the next day, December 5th, I took a series of soundings across the lake, proceeding from Camp CXLIII as far as the ice would allow me to go. The number of soundings was eight, and they were taken at equal intervals along a distance of 1375 m.; the depths obtained were as follows: — 3.69, 18.9, 20.00, 20.45, 2 1.39, 21.55, 20.00 and 17,45. The thickness of the ice proceeding from the shore out towards the middle of the lake was I t. r, 9.9, 7.5 and 3.8 cm., the value 7.5 cm. holding for five of the holes that we hewed. Immediately south of the last hole, where the ice already bent alarmingly under our weight, there came a long strip of open water, about 3o m. across. On the far side of it there was another expanse of ice, which reached all the way to the southern shore. Thus along this measured line the maximum depth amounted to 21.55 m.; and the reason why I consider this to be the maximum depth is that the next sounding after it, the seventh, was only 20 m., while the last amounted to but 17.45 m., thus indicating a distinct rise towards the southern shore. The maximum depth of the lake will coincide pretty nearly with its middle; but the mean depth north of that is greater than the mean depth south of it. This might indeed be inferred from the character of the shores; for, whereas on the north there are steep rocks, on the south the lake is bordered by a fairly level plain overgrown with bushes. Measured in a straight line from north to south the breadth of the lake will not at this part exceed 1400 m.; but our line of soundings ran towards the S. 4o° E., to avoid a couple of holes. Hence from
IIIF Color HighRes
