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Show TRAVELS THROUGH UPPER CANADA: ahlc fact, tlut f:..:vcr:d of the olddl white inh :tbitants in his neighbourhood ckcl.trcd, prcvionfl y to th riling (Jf the l.tl c, that the year 179 5 would bc th • high yc.\r; and that in the fU1l\ll1Cl' or th.tt year, the L\h.: actually ~ltd rife to a very un ommon hci ~ht. ll' i:tid, howeve r, that he had rea.lon to think the riling of the L l'e o 1 this occ:tflun W<l wholly owing to fortuitou circumfb.nccs, and not to any regular eflahlifhcd law of natur ; and he conceived, that if the lake had not rifen a it had don e, )ct th :.: pc pie would have fancied, ncverthclcCs, that it wa in reality bighcr than ufual, as he fuppofcd they had ftncicd it tu be on former occaJions. lie was induced to form this opinion, he f:lid, from the following cir nmflance: When the lake had riCcn to fuch an unufual hei,rht in the year 179 5, he examined fevcral of the c ldcfl: people on the fuhjcct, and queflioncd them particularly as to the comparative height oC the waters on this and ~ nncr occafions. They all declared that the waters were not higher than they ufua1ly were at the time of their periodical riling; and they affirmed, that they had themfe.lv s feen them equally high before. Now a grove of trees, which .flood adjoining to this gentleman' garden, and mufl: at leafl: have been of thirty years rrowth, was entirely dcfiroyed this year by the water of the lake, that flowed amongfl: the trees; had the lake, therefore, ever rifen fo high before, this grove would have been then defiroyed. Thi circumfran e certainly militated fi:rongly againfl: the evidence which the people <rave as to the height of the waters; but it only proved tlut the WJters had rifl:n on this occaiion higher than they had done for thirty years prcct: ding; it did not prove that they had not, during that term, I:ift:n periodically above their ordinary level. What Mr. Carver relates concerning this fubjeB:, rather tends to onfinn the opinion that the waters of the lake do rife. '' I had like," he fays, " to have omitted a very extraordinary circumfiancc rdativc " to thefc firaits ;" the Straits of Michillimakinac, betwc n lakes Michigan and Huron. " According to obfervations made by the French, " whilfl: they were in pofTd1ion of the fort there, although there is no " diurnal flood or ebb to be perceived in thefe waters, yet fro n an exact " attention to their fiate, a periodical alteration in them has been dif- " covered. L A K E 0 N T A R I 0. " covered. It was obf-erved, that they arofe by gradual but almoft im" perceptible degrees, till they had reached the height of three feet; " this was accomplifhed in fevcn years and a half; and in the fame fpacc ~' of time they as gently decreafed. till they had reached their former " 1i tuation ; fo that in fifteen years they had com pletcd this incxpliu cable revolution. At the time I was there, the truth of th fc obfcr" vations could not be confirmed by the Engliih, as they had then been " only a few years in poffeffion of the fort; but they all agreed that " fome alterations in the limits of the firaits was apparent." It is to be lamented that fucceeding years have not thrown more light on the fubjett; for fincc the fort has been in our po!IdTion, per(ons competent to determine the truth of obfervations of fuch a nature have never ilaid a futlicient length of time there to have had it in their power to do fo. A long fcrics of minute obfervations arc neccfT..1ry to determine pofitivcly whether the waters of the lake do or do not rife and fall periodically. It is well known, for infhnce, that in wet feafons the waters rife much a hove their ordinary level, and that in very dry feafuns they fink confidcrably below it; a clofe attention, therefore, ought to be paid to the quantity of rain th:J.t f.111s, and to evaporation; and it ought to be afcertained in what degree the height of the lake is altered thereby; otherwife, if the lake happened to be higher or lower than ufual on the fcvcnth year, it would be impoflible to fay with accuracy whether it WL're owing to the fiatc of the weather, or to certain laws of nature that we arc yet unacquainted with. At the fame time, great attention ought to he paid to the fiate of the winds, as well in rcfj1cct to their dirctl:ion a to their velocity, for the height of the waters of all the lakes is materially affeeted thereby. At Port Eric, iituated at the e.Lfl:crn extremity of the lake of the i:1me name, I once obfervcd the wat ·rs to fi1ll full three feet in the courfc of a few hours npon a fudden change of th ~ind from the wcfl:ward, in which direction it had blown for many <lays, to the cafi:ward. Moreover, thefe obfcrvations ought not only to be made at one place on the borders of any one of the lakes, bnt they ought to be made at fcvcral different pbces at the fi1mc time; for tl1c P p 2 water~ |