164 Major Lachlan on the Rise and Fall of the Lakes. 
Art. XVI.—On the Periodical Rise and Fall of the Lakes ; by 
M 
agor Lacuian, Montreal. 
(Continued from p. 71.) 
Sucu continued to be the state of the question, till the institu- 
tion, by the American States, of those great patriotic works, the 
Geological Surveys of New York, Ohio, and Michigan, when the 
subject being taken up by the talented individuals employed in 
that duty, as far as their other immediate avocations would permit, 
with that spirit which ever distinguishes the lovers of science, I 
was enabled to glean many interesting additional particulars from 
their official reports, though, unfortunately, none sufficiently con- 
clusive to solve the great philosophical problem so long under dis- 
cussion. Among these I, of course rank first the eminent Amer- 
ican geologist, Professor Hall, from whose elaborate work, put 
forth under the enlightened auspices of the State of New York, 
I extract the following valuable remarks on the elevation and de- 
pression of the great Lakes:* 
“The fluctuating level of the waters of these Lakes has long 
excited attention ; and many speculations have been hazarded to 
account for the phenomenon. The somewhat general belief that 
the periodical rise and fall in their waters occupy seven years ap- 
pears not to be founded on authentic observation. Sand-bars and 
beaches, or the inlets of certain bays, are regarded as the land- 
marks; and these being liable to fluctuation from accumulation 
and removal, it follows that no hypothesis, founded on such ob- 
servations, can be of any value. . . is nevertheless true 
that there are important. fluctuations in the Lake levels, which 
are unconnected with the temporary influence of winds. The 
tity of snow fallen during certain seasons has been considered a 
small degree of sunshine, the amount of evaporation being thus 
diminished, the Lakes remain ata high point. These causes, 
though perhaps satisfactory, and without doubt true, at least to a 
certain extent, do not always appear sufficient to account for the 
fluctuations which have been noticed. T'wenty-five or thirty 
years ago the beach of Lake Erie was a travelled highway beyond 
eetelo: but at this time it would be quite impossible to travel 
10 iC SHC... -s 
* See Hall’s Geology of New York, pp. 498 to 410. 
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