MEETINGS OF SOCIETIES. 499 
the sinking, and 6 miles from the lake, though still on the flat land, 
which evidently is part of its ancient bed, a well was sunk, and near the 
top of it gravel was found, and carried down to 18 feet, where it contained 
so much water that they could not sink any deeper. At the north end 
of the lake these conditions are found in duplicates almost exactly, only 
there the gravel ridges seem to be higher. The most recent of 
these gravel deposits at both ends cf the lake abut on to the western 
mountains, and extend thence obliquely across the old lake bed, thus 
cutting off from the main body portions of it which are now swamps. 
The southern one, however, does not hold water well, while the northern 
one has always been known as the wet lagoon, because it always con- 
tained water until last year, when Mr. Beit succeeded in draining it. 
With reference to the height of these ridges above the water now, I was 
unable to take any levels at the northern end of the lake; but at the 
south end I ran the level from the 1871 flood level to the top of the 
gravel ridge 197 feet, the rise being 22 feet 8 inches, thence down the 
other side of the ridge to the bed of the swamp, descending 18 feet & 
inches in 93 feet; the old swamp bed is, therefore, only 4 feet above the 
1871 level of the lake. I then took in eight places the difference in 
level between the present water and the 1871 level, and found the mean 
to be 11 feet 11 incheson February 20 this vear. The extremes of 
these measures differed four inches. Some were taken to the edge of 
the 1871 gravel as nearly as it could be determined, and others to the 
high water mark on the old dead trees. During the day the register 
shows a variation of level in the water of two inches, which, as it was 
rising and falling, was probably eliminated in the mean. If, therefore, 
we add together the differences between the present water level and that 
of 1871, between that and the top of the gravel ridge we find it is 34} 
feet, and at one time the lake must have been as high or nearly as high 
as that in order to pile up the gravel. At first it is difficult to see any 
reason for the formation of the gravel deposit where it is, but looking 
at the 1871 level, one sees the nucleus of another in a thin line of 
gravel about a foot thick; such a deposit on flat ground would grow, if 
the level of the water was at all constant, and gradually a ridge would 
be formed. The direction of these ridges at right angles to N.E. and 
S.E. winds points to a probable past when the winds were alternately 
from these directions during long periods, and as the gravel is made at 
the western edge of the lake and now at the ends, it must have been 
transported along the margin and thence out on to the flat country by 
the action of the waves. In the absence of levels it is impossible to say 
what was the extreme size of the lake in its wet period, but, I should 
think, at least 40 miles long and 10 or 12 wide. The steep hills which 
bound the lake on the west side are deeply furrowed by water, and 
afford striking evidence of a time when rain must have fallen in vastly 
greater abundance than it does at the present day. ach of these 
gullies, when examined, is found to have a more or less extensive delta, 
which has spread out laterally and into the lake, forming there a pro- 
jecting point opposite the gully. These are now covered with trees, and 
add very much to the beauty of the lake by their picturesque effect. In 
many cases, especially at the south end of the lake—that is, near 
Douglas House—these deltas are cut through by the watercourse which 
serves to carry off the rains of the present day, and these reveal 
distinctly the character of the deposit through which they run; showing 
