. 68 Major Lachlan on the Rise and Fall of the Lakes. 
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made on the progress of the elevation, as to whether there were 
preceding seasons of a character to produce it; and, therefore, 
after noticing various well-known periods at which remarkable 
elevations and depressions took place, such as in 1800, 1815, 
1820, 1828, and 1830, by way of proof of the periodical return 
of that phenomenon being regular or otherwise, he was obliged 
to come to the conclusion that, as far as facts go they are cer- 
tainly in favor of the popular theory, but that it rests on these 
facts alone, and is in many other points of view improbable and 
absurd ; and that we are therefore constrained to suppose, though 
destitute of the light of actual observation, that the fluctuations 
observed must have been cansed by unusually abundant rains and 
course.* : 
Having, in a previous page, quoted largely from Mr. Weld, I 
now proceed to notice the judicious remarks on the rise and fall 
of the Lakes by another intelligent British observer, Mr. McTag- 
gart, who, writing in 1828, sets out by at once affirming that 
“there are no tides in any of the Lakes—none, at least, from the 
moon’s influence; but that the floods of spring generally raise 
them from three to four feet. It is stated that. Lake Ontario rises 
i he 
fallen for many years before; and that there was little sunshine 
throughout the season; and I, consequently, concluded that the 
exhalations from the: Lake were-not so copious. There was an- 
other circumstance that puzzled me. _ Lake Ontario, and indeed, 
all the Lakes were up to their very highest surface marks, but the 
rivers flowing out of them were not. Those surface marks were 
very obvious on the rocky shores of the Lakes, drawn like so 
many chalk lines by Nature herself. 
‘“‘ Rivers do not rise exactly from the same cause as Lakes. If 
in spring the snow melts off the country on a sudden, and the 
‘ozen swamps break up and disembogue their contents, then the 
rivers will rise to their utmost height as water pours into them on 
all sides; but when the sun has effected this, they begin to fall. 
Lakes swell, it is true, from the same cause, but not with the same 
comparative haste; their surface being of great extent, the floods 
can only,spread over them by slow degrees; and if the sky keep 
* See American Journal of Science, vol. xx, pp. 218, 219. 
