REPORTS ON TORONTO HARBOUR, 



17 



pies. A barrier may have then existed at its outlet, where probably 

 the Thousand Islands are now seen, over the top of which the primeval 

 St. Lawrence flowed ; this great river, rushing over the barrier with 

 tremendous velocity, would, through course of time, wash away its 

 softer parts, and leave standing those numerous isolated rocks and 

 picturesque islands which, now covered with foliage, adorn so much 

 the landscape of that section -of the country. If this be not the ap- 

 proved way of accounting for the lowering of the level of the waters, 

 a gradual upheaval of the land generally, or even a subsidence of the 

 ocean may be brought forward ; it is unnecessary for our present pur- 

 pose, however, to enter into a geological disquisition on this point, if 

 we allow that the whole of the country bordering on Lake Ontario was 

 at one time submerged under the same extensive sheet of water ; and 

 that the level of this great lake, or it may be this arm of the ocean, 

 was through course of time depressed, and its outline contracted until 

 it was reduced to the present Ontario. A supposition so strongly sup- 

 ported by the discovery of several ancient beach lines, terraces and 

 parallel ridges in the vicinity of Toronto and other parts of the country, 

 at various, but corresponding levels, that it may, without much diffi- 

 culty be admitted. 



As the land gradually emerged, its appearance would be bleak in 

 the extreme ; a flat or but slightly undulating surface unbroken by 

 rivers or ravines, and uncovered, for a length of time with vegetation ; 

 on the ancient shallows of the great lake various kinds of plants would, 

 through course of time, take root, grow up and wither ; the continued 

 reproduction and decay of which would gradually coat the surface 

 with organic matter, and thus enriching the soil, enable it to produce 

 more luxuriant vegetation. Now, (prior to the settlement of the 

 country,) after a lapse of many centuries, we find the great hardwood 

 forest growing over soils of an argillaceous character, and the ancient 

 sand shoals of the great lake clothed with lofty pine. 



We can easily imagine the general character of the present shores of 

 Lake Ontario, when they first became dry land — a vast undulating 

 plane ascending as at present from the Lake into the interior, but 

 totally devoid of water channels for the surface drainage — here a bed 

 of clay — there a tract of sandy soil ; and as it is only reasonable to 

 suppose that rains fell in those days as at present, the water produced 

 by them on the surface, in flowing from a higher to a lower level, would 

 most easily wash out channels in the softest material ; and these little 

 streams, collecting together in their downward course towards the 

 Lake, would form the commencement of a river course. 



The newly formed rivers, having the same fall towards the Lake as 

 the surface itself, their beds being but slightly under it, would be 

 much more rapid than they are now, and rushing down with violence 

 after thaws and heavy rains, would, proportionally with their greater 

 rapidity, during the first years of their existence, be more effective in 

 scooping out the sand drift, and transporting it to the Lake ; from 

 year to year the water channels would thus grow larger and larger, 

 and although the rivers, as they were depressed, lost much of their 

 force and rapidity, yet continually undermining the banks and trans- 

 porting the debris downwards, would, through course of ages, form 

 those deep ravines in which many of them now flow. 



That the rivers in this section of the country have originated in this 

 manner, is infeired from the fact, that they are found almost univer- 

 sally to flow in flat-bottomed vallies or ravines, the banks of which 

 are the abrupt terminations of the level country on each side ; and 

 that these ravines are generally found where the drift is of a light and 

 sandy nature. 



The accompanying section across the River Don, taken a little above 

 the Cemetery, will show clearly the first proposition ; the second also 



is established by the well-known character of the soil of which the 

 banks are composed. The surface of the country extends for miles 

 to the right and left of the river without any material change of level, 

 except where broken by a secondary ravine of a tributary stream. 

 Doubtless, then, the inference is correct as far as regards the Don, 

 and that the dotted line stretching from bank to bank on the drawing, 

 was the surface prior to the scooping out of its channel. 



Section across the Don about l 1 .*,' miles from its mouth. 



a. The valley of the Don about a % of mile wide, and upwards of 100 feet deep— the 

 river here is on a level with Lake Ontario. 



6. A tributary of the Don, running through Yorkville, it is cut obliquely by the sec- 

 tion and forms a junction with the Don about )4 a mile further down. 

 The dotted line is about 120 feet higher than the Lake, and the surface maintains 



very nearly the same level for a long distance on either side in a direction parallel to 



the shore, with a gentle slope at right angles to it — on part of this slope the City of 



Toronto is built. 



Nor is the Don singular in these respects ; of all the streams I am 

 acquainted with to the east and west of Toronto, the same scooping 

 out of the ravines can be shown, and generally the same sandy charac- 

 ter of the country immediately traversed, as indicated by the dark 

 green belts of pine running into -the interior of the country through 

 the hardwood forest which flourishes better on the heavier soils. And 

 here, without digressing much from the subject, one can scarcely 

 avoid observing very apparent marks of design — the adapting of the 

 pine to grow on soils unfitted for cultivation, and the leading of rivers 

 through pine-bearing soils, thus enabling the settler to take advantage 

 of the various properties of running water in conveying and preparing 

 the most useful of all timbers for his manifold purposes. 



The v lley of the Don is from a quarter to half a mile in width, with 

 abruptly rising banks, from 100 to 200 feet and upwards in height, 

 the scooping out of which implies the removal of many hundred millions 

 of cubic yards, a quantity so immeasurably great when brought into 

 comparison with the agent of removal — a stream (when not dammed 

 up) only about 50 feet wide, that it appears altogether irreconcilable 

 with the inference drawn ; more especially is it so, when we know that 

 'he annual quantity of matter brought down by the Don is at present 

 inconsiderable. If, however, we bear in mind that, without assuming 

 a greater volume of water to have flowed in its channel than now, the 

 transporting power of the Don must formerly have been very much 

 greater by reason of its greater descent and rapidity; and, if it can he 

 shown that many ages have elapsed since it first came into existence, 

 the conclusion come to may be taken as rational and correct. 



It may seem difficult — nay, almost impossible — to estimate, however 

 roughly, the time which has elapsed since the Don commenced to 

 flow ; but if we can arrive at the age of any other river emptying its 

 water into Lake Ontario from a source equally high, the problem is 

 solved. When the great Lake already mentioned, subsided from its 

 high level, then, and not till then, did the Niagara, the Don, and other 

 cotemporary rivers make their appearance. Since that epoch the 

 Niagara has cut a deep channel for seven miles through the solid rock; 

 its annual recession has been ascertained approximately, and from 

 these data its age has been roughly determined. "We may turn to 

 the deep ravine," says Lyell, "and behold therein a chronometer 

 measuring rudely, yet emphatically, the vast magnitude of the interval 



