The Niagara River flows from Lake Erie to Lake Ontario. The shore of Erie is more than 300 feet higher than the shore of Ontario; but if you pass from the higher shore to the lower, you do not descend at a uniform rate. Starting from Lake Erie and going northwards, you travel upon a plain not level, but with only gentle undulations until you approach the shore of Lake Ontario, and then suddenly you find yourself on the brink of a high bluff, or cliff, overlooking the lower lake and separated from it only by a narrow strip of sloping plain.
Where the Niagara River leaves Lake Erie at Buffalo and enters the plain, a low ridge of rock crosses its path, and in traversing this its water is troubled; but it soon becomes smooth, spreads out broadly and indolently loiters on the plain. For three-fourths of the distance it cannot be said to have a valley, it rests upon the surface of the plateau; but then its habit suddenly changes. By the short rapid at Goat Island and by the cataract itself the water of the river is dropped two hundred feet down into the plain, and thence to the cliff at Lewiston it races headlong through a deep and narrow gorge. From Lewiston to Lake Ontario there are no rapids. The river is again broad, and its channel is scored so deeply in the littoral plain that the current is relatively slow, and the level of its water surface varies but slightly from that of the lake.
The narrow gorge that contains the river from the Falls to Lewiston is a most peculiar and noteworthy feature. Its width rarely equals the fourth of a mile, and its depth to the bottom of the river ranges from two hundred to five hundred feet. Its walls are so steep that opportunities for climbing up and down them are rare, and in these walls one may see the geologic structure of the plateau.
The contour of the cataract is subject to change. From time to time blocks of rock break away, falling into the pool below, and new shapes are then given to the brink over which the water leaps. Many such falls of rock have taken place since the white man occupied the banks of the river, and the breaking away of a very large section is still a recent event. By such observation we are assured that the extent of the gorge is increasing at its end, that it is growing longer, and that the cataract is the cause of its extension.
This determination is the first element in the history of the river. A change is in progress before our eyes. The river's history, like human history, is being enacted, and from that which occurs we can draw inferences concerning what has occurred, and what will occur. We can look forward to the time when the gorge now traversing the fourth part of the width of the plateau will completely divide it, so that the Niagara will drain Lake Erie to the bottom. We can look back to the time when there was no gorge, but when the water flowed on the top of the plain to its edge, and the Falls of Niagara were at Lewiston.
We may think of the river as labouring at a task the task of sawing in two the plateau. The task is partly accomplished. When it is done the river will assume some other task. Before it was begun what did the river do?
How can we answer this question? The surplus water discharge from Lake Erie could not have flowed by this course to Lake Ontario without sawing at the plateau. Before it began the cutting of the gorge it' did not flow along this line. It may have flowed somewhere else, but if so it did not constitute the Niagara River. The commencement of the cutting of the Niagara gorge is the beginning of the history of the Niagara River.
The river began its existence during the final retreat of the great ice sheet, or, in other words, during the series of events that closed the age of ice in America. During the course of its history the length of the river has suffered some variation by reason of the successive fall and rise of the level of Lake Ontario. It was at first a few miles shorter than now; then it became suddenly a few miles longer, and its present length was gradually acquired.
With the change in the position of its mouth there went a change in the height of its mouth; and the rate at which it eroded its channel was affected thereby. The influence on the rate of erosion was felt chiefly along the lower course of the river between Lewiston and Fort Niagara.
The volume of the river has likewise been inconstant. In early days, when the lakes levied a large tribute on the melting glacier, the Niagara may have been a larger river than now; but there was a time when the discharge from the upper lakes avoided the route by Lake Erie, and then the Niagara was a relatively small stream.
The great life work of the river has been the digging of the gorge through which it runs from the cataract to Lewiston. The beginning of its life was the beginning of that task. The length of the gorge is in some sense a measure of the river's age.
The river sprang from a great geologic revolution, the banishment of the dynasty of cold, and so its lifetime is a geologic epoch; but from first to last man has been a witness to its toil, and so its history is interwoven with the history of man. The human comrade of the river's youth was not, alas! a reporter with a notebook, else our present labour would be light. He has even told us little of himself. We only know that on a gravelly beach of Lake Iroquois, now the Ridge Road, he rudely gathered stones to make a hearth and built a fire; and the next storm breakers, forcing back the beach, buried and thus preserved, to gratify yet whet our curiosity, hearth, ashes and charred sticks.
In these Darwinian days we cannot deem primeval the man possessed of the Promethean art of fire, and so his presence on the scene adds zest to the pursuit of the Niagara problem. Whatever the antiquity of the great cataract may be found to be, the antiquity of man is greater.
Where the Niagara River leaves Lake Erie at Buffalo and enters the plain, a low ridge of rock crosses its path, and in traversing this its water is troubled; but it soon becomes smooth, spreads out broadly and indolently loiters on the plain. For three-fourths of the distance it cannot be said to have a valley, it rests upon the surface of the plateau; but then its habit suddenly changes. By the short rapid at Goat Island and by the cataract itself the water of the river is dropped two hundred feet down into the plain, and thence to the cliff at Lewiston it races headlong through a deep and narrow gorge. From Lewiston to Lake Ontario there are no rapids. The river is again broad, and its channel is scored so deeply in the littoral plain that the current is relatively slow, and the level of its water surface varies but slightly from that of the lake.
The narrow gorge that contains the river from the Falls to Lewiston is a most peculiar and noteworthy feature. Its width rarely equals the fourth of a mile, and its depth to the bottom of the river ranges from two hundred to five hundred feet. Its walls are so steep that opportunities for climbing up and down them are rare, and in these walls one may see the geologic structure of the plateau.
The contour of the cataract is subject to change. From time to time blocks of rock break away, falling into the pool below, and new shapes are then given to the brink over which the water leaps. Many such falls of rock have taken place since the white man occupied the banks of the river, and the breaking away of a very large section is still a recent event. By such observation we are assured that the extent of the gorge is increasing at its end, that it is growing longer, and that the cataract is the cause of its extension.
This determination is the first element in the history of the river. A change is in progress before our eyes. The river's history, like human history, is being enacted, and from that which occurs we can draw inferences concerning what has occurred, and what will occur. We can look forward to the time when the gorge now traversing the fourth part of the width of the plateau will completely divide it, so that the Niagara will drain Lake Erie to the bottom. We can look back to the time when there was no gorge, but when the water flowed on the top of the plain to its edge, and the Falls of Niagara were at Lewiston.
We may think of the river as labouring at a task the task of sawing in two the plateau. The task is partly accomplished. When it is done the river will assume some other task. Before it was begun what did the river do?
How can we answer this question? The surplus water discharge from Lake Erie could not have flowed by this course to Lake Ontario without sawing at the plateau. Before it began the cutting of the gorge it' did not flow along this line. It may have flowed somewhere else, but if so it did not constitute the Niagara River. The commencement of the cutting of the Niagara gorge is the beginning of the history of the Niagara River.
The river began its existence during the final retreat of the great ice sheet, or, in other words, during the series of events that closed the age of ice in America. During the course of its history the length of the river has suffered some variation by reason of the successive fall and rise of the level of Lake Ontario. It was at first a few miles shorter than now; then it became suddenly a few miles longer, and its present length was gradually acquired.
With the change in the position of its mouth there went a change in the height of its mouth; and the rate at which it eroded its channel was affected thereby. The influence on the rate of erosion was felt chiefly along the lower course of the river between Lewiston and Fort Niagara.
The volume of the river has likewise been inconstant. In early days, when the lakes levied a large tribute on the melting glacier, the Niagara may have been a larger river than now; but there was a time when the discharge from the upper lakes avoided the route by Lake Erie, and then the Niagara was a relatively small stream.
The great life work of the river has been the digging of the gorge through which it runs from the cataract to Lewiston. The beginning of its life was the beginning of that task. The length of the gorge is in some sense a measure of the river's age.
The river sprang from a great geologic revolution, the banishment of the dynasty of cold, and so its lifetime is a geologic epoch; but from first to last man has been a witness to its toil, and so its history is interwoven with the history of man. The human comrade of the river's youth was not, alas! a reporter with a notebook, else our present labour would be light. He has even told us little of himself. We only know that on a gravelly beach of Lake Iroquois, now the Ridge Road, he rudely gathered stones to make a hearth and built a fire; and the next storm breakers, forcing back the beach, buried and thus preserved, to gratify yet whet our curiosity, hearth, ashes and charred sticks.
In these Darwinian days we cannot deem primeval the man possessed of the Promethean art of fire, and so his presence on the scene adds zest to the pursuit of the Niagara problem. Whatever the antiquity of the great cataract may be found to be, the antiquity of man is greater.
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