1854.] 



ON THE PERIODICAL RISE AND FALL OF THE LAKES. 



299 



or to give a probable error. . . Tbe geographical position of 

 Lake Erie in reference to the prevailing winds is the cause of 

 irregularities in the annual rise and fall of its waters. Its ge- 

 neral course being north-east and south-west, discharging at the 

 north, the steady west wind of the fall accelerates the flow of 

 water from this Lake, at the same time retarding its supply from 

 the other Lakes. 



"It has been asserted that there exists in the Lakes, as in the 

 Ocean, a daily or lunar tide. Whether it is true when applied to 

 Huron, Ontario, or other lakes, is not perhaps entirely settled. 

 The observations I have been enabled to make on Lake Erie, 

 and the uniform testimony of the waterman and harbour work- 

 men coincide in denying the existence of any change resembling 

 the Oceanic tide, and Mr. Davies, the Collector of Customs, writes 

 decidedly: ' This is not the fact; the examination of the tide- 

 waiter kept at our office, and observations, made almost hourly 

 since August last, enable me to assert, without fear of contradic- 

 tion, that there is no tide upon Lake Erie.' " 



It will be perceived that I already happen to possess more 

 accumulated information on the vicissitudes of Lake Erie, to 

 which my own attention aud reflections had been more particu- 

 larly directed, than of all the, rest of our great Mediterranean seas 

 put 'together ; and I have now the additional satisfaction of turn- 

 ing to the investigations of my more immediate neighbours, tho 

 State Geologists of Michigan, and more especially of their 

 talented chief, the lamented late Dr. Houghton, and his able 

 assistant and topographer, Mr. Higgins. 



From the first Report of the former, however, I can only ven- 

 ture to point to the following naked paragraphs, on the change 

 of elevation in the waters of the Lakes, as equally applicable to 

 Canada as to the American States.* 



"The great interest which this subject possesses, in connection 

 with our Lake Harbours, as well as with those agricultural in- 

 terests situated upon the flat lands bordering the Lakes and 

 Rivei-s, may be a sufficient apology for the introduction of the 

 following facts and reflections npon the subject. An accurate 

 and satisfactory determination of the total rise and fall of tho 

 waters of the Lakes is a subject, the importance of which, in con- 

 nection with some of our works of internal improvement and 

 harbours, can at this time scarcely be appreciated. 



" Much confusion is conceived to have arisen in the minds of 

 a portion of our citizens, in consequence of a confounding of the 

 regular annual rise and fall to which the waters of the Lakes 

 are subject.with that apparently irregular elevation and subsidence 

 which only appears to be completed in a series of years; changes 

 that are conceived to depend upon causes so widely different, 

 that, while the one can be calculated with almost the same cer- 

 tainty as the return of the seasons, the other can by no means bo 

 calculated with any degree of certainty. 



" It is well known to those who have been accustomed to 

 notice the relative height of the water of the Lakes, that during 

 the winter season, while the flow of water from the small streams 

 is either partially or wholly checked by ice, and while the springs 

 fail to discharge their accustomed quantity, the water of the 

 Lakes is invariably low. As the spring advances the snow that 

 had fallen during the winter is changed to water, the springs 

 receive their accustomed supply, and the small streams are again 

 opened, their banks being full in proportion to the amount of 

 snow which may have fallen during the winter, added to the 



* See Geological Report of Michigan for 1839, p. 20 to 22. 



rapidity with which it may have been melted. The water of 

 the Lakes, in consequence of this suddenly increased quantity 

 received from the immense number of tributaries, commences 

 rising with the first opening of the spring, and usually attains its 

 greatest elevation — at least in the upper Lakes — sometime in 

 the month of June or July. As the seasons advance, or during 

 the summer and a large portion of the autumnal months, evapo- 

 ration is increased, and the amount of water discharged by the 

 streams lessened, in consequence of which the water of the Lakes 

 falls very gradually until the winter again sets in, when a still 

 greater depression takes place, from the renewed operations of 

 the causes already mentioned. 



"Tho extreme variation in the height of the water from winter 

 to summer is subject to considerable change, according as the 

 winters may vary from cold and dry to warm and wet; but 

 during the past eight years it may be estimated at two feet. 



" The annual rise and fall of the waters of the Lakes, depen- 

 dent, as it manifestly is, upon causes which are somewhat uniform 

 in their operation, must not be confounded with that elevation 

 and depression to which the waters are subject, independent of 

 causes connected with the seasons of the year. These latter 

 changes, which take place more gradually, sometimes undergo- 

 ing but little variation for a series of years, are least liable to be 

 noticed, unless they be very considerable; but with respect to 

 consequences, they are of vastly more importance, since they are 

 subject to a larger and more permanent range. 



"That the waters of the Lakes, from the earliest settlement of 

 the country have been subject to considerable variation in rclativr 

 height is well known. At one time the belief was very general 

 that these changes took place at regular intervals, rising for a 

 space of seven years, and subsiding for a similar length of time: 

 a belief which would appear to be in consonance with that of 

 the Indians, and with whom it, no doubt, originated. It is not 

 wonderful that a subject, the causes of which are so little com- 

 prehended by our natives should be invested with an air of mys- 

 tery, or that an error once propagated, in consequence of the 

 long series of years required to bring about any considerable 

 change, could scarcely be eradicated. While the idea of that 

 septennial rise and fall must be regarded as founded in error, it 

 is nevertheless true, that from the earliest records, the height of 

 the Lakes has been subject to a considerable variation, usually 

 rising very gradually and irregularly for a series of years, aud 

 after that falling in a similar, but more rapid, manner." 



Dr. Houghton concludes a number of other excellent elucida- 

 tory remarks, by observing, with regard to the succession of 

 previous cold and wet seasons which produced the great rise 

 in 1838 — that, " when we take into consideration, in connection 

 with the causes enumerated, the fact that during the wet years 

 evaporation must have been less than during the dry ones, it 

 may be fairly presumed that sufficient apparent causes have 

 existed to produce all the results noticed; and we may add, 

 should such a succession of dry and warm seasons follow, we 

 may look with certainty for a return of the Lakes to the former 

 low level." 



In consequence of the great length of the foregoing quotation, 

 I must be content with giving only the following abridged and 

 disjointed particulars on the same subject from Mr. Higgins' 

 Reports of 1839 and 1841:— "That interesting question," the 

 periodical rise and fall of the Lakes, has given rise to a variety 

 of curious speculations. The inference drawn from the folio win'" 

 data, it is presumed, will not be altogether inconclusive. Calcu- 



