540 
BULLETIN OF THE BUREAU OF FISHERIES. 
Our observations on Seneca Lake were made in the deep water off North Hector. 
In Cayuga Lake they were made off Sheldrake and King Ferry. 
For the details of the hydrography, see p. 598. 
Owasco Lake (pi. cxii). — Owasco Lake is the smallest of the six major lakes, having 
about 70 per cent of the length of Skaneateles and Canandaigua Lakes. Its mean 
breadth is, however, somewhat greater, so that its area is about 70 per cent of that of 
Skaneateles Lake, its neighbor to the east. It is also the shallowest lake (54 meters, 
177 feet), although Keuka Lake exceeds it by less than 2 meters in maximum depth, 
and a little more than i meter in mean depth. It has the form typical of these lakes — 
a broader, rather shallow northern part extending into the lower country, and a narrow 
south part with steep sides. The valley, however, lies in that depression of the high- 
land which includes the north parts of Seneca and Cayuga Lakes. Its banks are, 
therefore, on the whole, lower than those of any of the other lakes, although of the same 
general character. The valley extends about 30 kilometers (18 miles) to the south, 
and with steeper slopes than any of those found immediately adjacent to the water. 
Near the lake the steep slope at the bottom never exceeds 100 meters, and is usually 
much less, and above this the slopes are gradual and do not rise to elevations much 
exceeding 200 meters above the lake. The lake itself is about 100 meters above Cayuga 
Lake, its neighbor to the west, and less than half as much below Skaneateles Lake. 
The outlet is controlled by a dam, and the lake is the source of water supply for 
the city of Auburn, which lies at its north end. The south end of the lake is somewhat 
silted up by alluvium brought down by the inlet, as is shown by the form of the 25-foot 
contour, and the valley is probably deeply filled with loose materials. 
In a report made in 1909 to the city of Auburn, Mr. G. P. Whipple computed the 
volume of Owasco Lake as equal to about 200,000,000,000 gallons, which would equal 
about 2,670,000,000 cubic feet. This computation is based on the same survey as ours, 
and is somewhat smaller than our estimate. (See table i.) Whipple’s diagram, how- 
ever shows the volume of the lake as slightly larger than our figures. 
Our observations in 1910 were made off Wyckoff, and temperatures were taken 
there in the winters of 1911 and 1912. Four series of temperatures were taken in 1911, 
the first near Rice Point at the south, and the last near the northern limit of the 
loo-foot contour. 
For the details of the hydrography, see p. 598. 
Keuka Lake (pi. cxv). — Keuka Lake, which drains into Seneca Lake, lies about 
80 meters above it. The stream which carries its water flows through a narrow post- 
glacial gorge and empties into Seneca Lake near Dresden. 
Keuka is the largest of the lakes after Cayuga and Seneca, and it is also the 
narrowest. It is the only lake whose outline is irregular. Its west arm, though the 
shorter, is the deeper, the 150-foot contour extending close to the northern end. The 
lake lies, as a whole, farther to the south than does any other of the district, and both 
branches of the basin are narrow to the extreme north end, since the valley does not 
widen out on the northern face of the plateau. It is one of the shallowest of the six 
major lakes, being less than 2 meters deeper than Owasco. The under-water slopes of 
