REPORTS ON TORONTO HARBOUR 



ing : " To the geological reader it will require no attempt to prove 

 t^his the ancient beach of Lake Ontario, or a body of water, perhaps 

 an arm of the ocean, which once stood at this elevation ; such 

 occurrences are well known elsewhere ; but there are many persons 

 in western N"ew York, and some grave critics among the number, 

 who prefer to explain this by supposing some stupendous uplift- 

 ing of the strata in this line from Sodus Bay to Niagara River." 

 Further on (page 351) Mr. Hall states that "The elevation of this 

 ridge above Lake Ontario has been variously estimated from one 

 hundred to two hundred feet. In 1838, through the kindness of 

 Mr. Barrett, I obtained the elevation of the ridge north of Lock- 

 port, which is about one hundred and sixty feet above Lake On- 

 tario." 



It is probable that the formation of the New York ridge above 

 described was contemporaneous with the lowest terrace of the 

 Scarboro' heights, and may not the persistant layers of water-worn 

 pebbles described before, as being about ten feet below the surface 

 of the plateau, be the ancient beach of Lake Ontario at its former 

 altitude ? Is it reasonable to suppose that when by a slow uphea- 

 val of the country, the level of Lake Ontario became comparatively 

 lower and lower, the strata of alternating sand and gravel and blue 

 clay forming so large a portion of the cliffs of the lowest terrace, 

 would have remained persistant, and permitted the land to fall in 

 easy slopes to the present level? Is it not rather to be supposed 

 that its shores would have been terraced and abrupt like those de- 

 scents which are to be seen about four miles from Toronto, where 

 the lowest terrace leaving the Lake crosses the road from Toronto to 

 Kingston ? If this were the case, and there does not appear to be 

 any reasonable objection to the hypothesis, the lowest terrace in- 

 stead of descending in easy slopes when the land became elevated 

 would form at least two distinct terraces abruptly bounded by de- 

 clivities of sand, precisely like the abrupt declivities seen on the 

 Kingston road near the eastern extremity of Ashbridge's bay, 

 which are nothing more or less than the abrupt sandy shores of the 

 ancient Lake as the land slowly rose from beneath the bed of a 

 Tertiary estuary or ocean. 



Under such circumstances the existence of any promonotory be- 

 comes very doubtful, and the coast line would appear to assume 

 an extension commensurate with the former extension of the 

 whole northern coast of Lake Ontario, which in its earlier develop- 

 ment extended probably nearly uniformly a short distance Lake- 

 wards. The protection afforded by Lake beaches during periods 

 of low water is so great that it may truly be said that the cliffs or 

 bluffs of the coast are only submitted to the denuding action of 

 atmospheric forces during those epochs, an action which tends to 

 give them the form and conditions essential to the growth of vege- 

 tation, which, in not a few instances, extends without the occur- 

 rence of cliffs or even of quarternary formations to the very shores 

 of the Lake. 



Other objections might be advanced against the existence of a 

 promontory or even a considerable extension of the coast of the 

 Scarboro' heights Lakewards since their emergence. Such for 

 example as the great depth of water which exists in the Lake to 

 the south of the Scarboro' heights. 



Lieutenant Herbert clearly shows soundings to the depth of 48 

 feet within a mile of the coast, and in one locality, west of the 

 Highland Creek, the great depth of 120 feet is recorded within 

 two miles of the coast ; what denuding operations can have pro- 



duced these great depths since the assumption of the present level 

 of Lake Ontario if the land extended Lakewards to a considerable 

 distance, even half of the distance assigned by Mr. Fleming (about 

 two miles — see section and scale) during that epoch ? The occur* 

 rence, it is said, of tertiary blue clay within two or three hundred 

 yards south of Ashbridge's Bay is another objection which, com- 

 bined with the known dip of the Silurian rocks in that locality, 

 suggests grave doubts as to the former extension of the land to a 

 degree consistent with the idea of a promontory.* 



Mr. Fleming's views of the origin of the delta of the Don are also 

 scarcely consistent with the probable topographical condition of the 

 country, when the Lake assumed its present level. The supposi- 

 tion is not admissable that the country rose from beneath a tertiary 

 ocean (see Geological Reports for 1845-6) in a sudden and violent 

 manner. It occupied, most probably, a vast epoch of time ; 

 if it emerged at twice the rate at which Sweden is now becoming 

 elevated, namely at the rate of five feet in a century near the 

 North Cape, and a few inches in a century near Stockholm, (see 

 Lyell's second voyage to the U.S., Vol. II., page 194, New York 

 Edition), it -would have required 32 centuries for the hills in 

 Scarboro' Township to have emerged ; or if we take the lower and 

 perhaps best defined sea beach, the one of the lowest plateau, 160 

 feet above the present lake level, it would still have embraced 16 

 centuries, and this too upon the supposition that the rise was con- 

 tinuous, which is known not to have been the case, as lower 

 beaches testify. During that period, how would rains, snows, and 

 dews drain away from a country "totally devoid of water-channels 

 for surface drainage," as Mr. Fleming supposes when he assumes 

 that the Don began to exist when the Lake had acquired its present 

 level (Can. Jour., Vol. II., page 106). The Don, together with all 

 the rivers and streams of any magnitude which now flow into Lake 

 Ontario, began their existence with the uprising land and grew with 

 its growth, excavating the Valleys through which they now flow to 

 within a few feet of their present level, during the successive 

 epochs of the subsidence of the Lake from its former vast extension. 

 The detritus of the Don and other streams, brought down durinc 

 higher Lake levels, forming sand-bars and mud-flats, which are 

 now pine clad ridges and the cleared farms of thriving settlers. 

 On the south shore of Lake Ontario the valleys of streams which 

 fell into the Lake when it stood at an elevation of 160 feet hio-her 

 than at present are plainly visible. Mr. Hall says, "The inter- 

 ruptions in the continuity of the ridge, from the passage of small 

 streams are numerous throughout its whole extent. Many of these 

 streams were doubtless discharging their waters into the Lake at 

 the time of the formation of the ridge, and have thus kept an open 

 passage, others have been closed up during its deposition and 

 formed little ponds upon the inland side, which, subsequently 

 becoming more powerful, have burst through the barrier and car- 

 ried away large portions of it." (Geology of the 4th District, pace 

 350.) 



It is suggested that the term 'delta' is altogether a misnomer, 

 leading to the idea that the River Don has brought down materials 

 from its excavated valley and deposited them at its mouth, and 

 elevated them above the surrounding waters, like the Nile and the 

 Mississippi, only on infinitely smaller scale. 



Now, the banks of the Don at its mouth are of tertiary yellow 

 and blue clay, and there was a time no doubt, not veiy far removed 



* See Appendix, Note E. 



