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THE OLD NORTHWEST.

I.

NORTH AMERICA IN OUTLINE.

NORTH AMERICA is easily separable into three very plainly marked physical divisions. The Pacific Highlands, which are a vast plateau surmounted by the Rocky and Sierra Nevada Mountain systems, extend from the Arctic Ocean to the Isthmus of Panama, and form the primary feature of the continent. The Atlantic Highlands, consisting of the Labrador Plateau and the Appalachian Mountain system, with the adjacent eastern slope, extend from Labrador almost to the Gulf of Mexico, and form the secondary feature. Between the Pacific Highlands and the Atlantic Highlands, extending from the southern Gulf to the northern Ocean, 5,000 miles in length by 2,000 in breadth at the widest part, and opening out like a fan to the north, is the Central Plain.

The Central Plain is also easily separable into three parts. First, the Arctic Plain descends by easy slopes from the wavy elevation called the Height of Land, north and northeast to the Arctic Ocean and Hudson Bay. Secondly, south of the Height of Land and a second similar elevation that takes off from it, near the head of Lake Superior, and sweeps southeast and northeast until it unites with the Appalachian Mountains in Northern New York, the Mississippi Valley falls away gently to the Gulf of Mexico. Thirdly, between the Arctic Plain and the Mississippi Valley lies the Basin of the Great Lakes, that is lengthened eastward in the St. Lawrence Valley.

The two sides of the continent, as divided by the eastern ranges of the Rocky Mountains, present the strongest contrasts. The western side consists of great mountain chains, attaining high elevations, with short and abrupt descents to the Pacific Ocean; the eastern side is a vast plain, descending to the Arctic and Atlantic Oceans and the Gulf of Mexico, by long and easy lines, save in the southeast, where it is interrupted by the moderate elevation of the Appalachian Mountains. Straight lines can be drawn from the Arctic Ocean to the Gulf of Mexico, from the southern shore of Lake Ontario to the Rio Grande, and from the source of the Ohio to the source of the Kansas, that will at no point rise 2,000 feet above the level of the sea. In fact, the geographer passes over whole States without finding any elevations of surface that he need represent upon a map intended for common purposes.

On the one side, and particularly south of 49° north latitude, the coast line is remarkably regular; on the other side, remarkably irregular.

On the west, few rivers descend to the sea, and not one of these cuts through the mountain masses and reaches the interior; on the east, every subdivision of the Central Plain is traversed by a great natural water-way. Hudson Strait, Hudson Bay, and the Nelson-Winnipeg River system together reach the very foot-hills of the Rocky Mountains. The noble St. Lawrence, cutting through the Appalachian Mountains, opens a channel for the Great Lakes to discharge their floods, and for man to ascend to the central parts of the continent. The Mississippi-Father of Waters—with his 35,000 miles of navigable affluents, gives ready means of access to every part of the great valley that bears his name. If three men should ascend these three water-ways to their farthest sources, they would find themselves in the heart of North America, and, so to speak, within a stone's-throw of one another. One of these water-ways has played hitherto no considerable part in the affairs of civilized men; but the

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other two are as prominent in the history of America as they are in its geography.

The world scarcely offers a parallel to the ease and celerity with which the passage can be made from the upper waters of any one of these great water-ways to either of the others. "The Great Lakes occupy an elevated plateau, the summit, in fact, of the vast expanse of land which spreads out between the Alleghanies and the Rocky Mountains; no large streams flow into them, and they drain limited areas; "1 and their basins are separated from the regions north and south by water-sheds that in no point rise to the dignity of mountains. Lake Superior is 900 feet above the Gulf of St. Lawrence; Lake Itasca, Pittsburg, and Cairo are 1650, 700, and 300 feet respectively above the Gulf of Mexico. From Omaha west along the Platte River, the Union Pacific Railroad ascends by a grade of five feet to the mile; while from St. Paul northwest to the Yellowstone, the ascent is but two feet to the mile. In Ohio, Indiana, Illinois, and Wisconsin the streams flowing in opposite directions often head in the same swamps; and in times of high water it would almost be possible to push a flat-bottomed boat from the Lake Basin into the Mississippi Valley. The highest level of the Ohio Canal is 395 feet, the highest level of the Miami Canal, 380 feet, above Lake Erie. A simple pump suffices to carry the sewage of Chicago to a level where gravitation takes it to the Mississippi. Lake Michigan once had an outlet to the Gulf of Mexico, and should the "Hennepin Canal" ever be built, it will be an artificial outlet.

In the days when the Northwest was discovered and explored, and again in the days when it was settled, the short and easy portages between the northern and southern streams, scattered all the way from Western New York to Minnesota, were of very great importance.

The Appalachian system consists of several chains or

1 Hubbard Memorials of a Half Century, 3.

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