To the west of the Alleghany Mountains is the great valley of the Ohio and Mississippi, sloping gradually towards the Mississippi, and rising again towards the Rocky Mountains. The distance in a direct line from the Alleghany Mountains, east of Pittsburg, to the Rocky Mountains, is about 1400 miles. The height of the eastern section above the level of the sea, is from 500 to 800 feet. The western section becomes very elevated, the base of the Rocky Mountains being estimated at 3000 feet. The general course of the Rocky Mountains has been already described. For a considerable distance from the Mississippi the chain is not very elevated, but toward the head waters of the Arkansas the country rises to a great height, and many of the peaks are constantly covered with snow. In that part of these mountains where they are wholly within the United States, they extend in a N. W. direction from 42° to 49° N. L. a distance of 650 miles, and they average 300 miles in breadth. It is probable that the base in this quarter is from 3500 to 4000 feet high. The highest points that have been ascertained with ac curacy are, Highest peak, 12,500 12,000 The tops of both rise beyond the inferior limit of perpetual snow, which, in that lat. is estimated at 11,000 feet. The mountains on the north-west coast have a much lower base than the Rocky Mountains; but many of them are high, peaked, and very elevated. There is a considerable group of mountains called the Ozark, extending south-west, from St. Louis, on the Mississippi, toward the Warm Springs in Arkansas. Rivers and Lakes. In giving a general view of the rivers of the United States, it has been deemed proper to select those great streams which are general in their na ture, and flow through many of the states, leaving the minor streams to be noticed in the descriptions of the several states through which they pass. The principal lakes are formed by the St. Lawrence, and shall be noticed in the description of that river accordingly. River St. Lawrence. The head waters of this river are situated round Lake Superior. On the west is the river St. Lewis, which approaches within a few miles of the Savannah, a branch of the Mississippi. On the south the principal streams are Burntwood, Montreal, and Ontonagon. On the north side Portage and Redstone. Lake Superior is the largest body of fresh water on the globe, being about 350 miles long, and its mean breadth about 100, so that it contains about 35,000 square miles. The banks of this lake are generally lofty and romantic, and the water is very deep, so that it is navigable throughout its whole extent. From Lake Superior, the water issues at the east end, and by a very rapid current, which is interrupted by several small islands, or rather huge masses of rock; it runs through a channel of 27 miles, when it reaches Lake Huron. About the middle of this channel are the Falls of St. Mary, which oppose an effectual bar to the navigation, although the fall is only about 23 feet in the distance of half a mile. Lake Huron is, next to Lake Superior, the largest lake on the continent of America. Measuring from the entrance of the river to its outlet at Fort Gratiot, it is about 220 miles, and its mean breadth may be assumed at 90; the lake therefore contains nearly 20,000 square miles. Like Lake Superior, it has pure water and good navigation; and it is interspersed with numerous islands, some of them pretty extensive. To the westward of Lake Huron is Lake Michigan, a most singular appendage to the waters of this extraordinary river. This lake is wholly in the United States. Its head is situated in lat. 41° 35', be tween the states of Indiana and Illinois, and its outlet is at Michilimackinack, distant three hundred miles. Its mean breadth, including Green Bay, is about fifty miles, so that its area is about 15,000 square miles. The water is clear and transparent, and the navigation is good through the whole extent. Returning to Lake Huron, the river issues from its southern extremity, through St. Clair River, which is about three-quarters of a mile broad, and pretty deep, with a gravelly shore and transparent water; and its surface is chequered with a number of beautiful islands. This river runs about 32 miles and falls into Lake St. Clair. Lake St. Clair is a beautiful sheet of water, about 30 miles in diameter, and being in area about 900 square miles. Out of this lake, the waters again assume the form of a river called Detroit, which continues first a south-west and then a southerly course to Lake Erie, distant about 27 miles. This is also a deep broad river, greatly enlarged, towards the southern extremity, and embodying several important islands. Detroit is handsomely situated on its west bank, about 5 miles from Lake St. Clair, and Amherstburg is on the east bank near the lower extremity. The waters are now expanded into the large and important Lake Erie, a most beautiful sheet of transparent water, about 230 miles long, and averaging about 45 broad; its area being about 10,350 square miles. The medium depth is about 20 fathoms, and its bottom is generally rocky, which renders anchorage precarious. At the east end of Lake Erie, on a commanding eminence, stands Buffaloe, and two miles below, Black Rock,* on the side of the United States; and on the opposite side Fort Erie. Between these positions, the water again assumes the form of a river, and is called Niagara. At the outlet * The Erie Canal terminates here and at Buffaloe. GREAT FALLS OF NIAGARA. of Lake Erie it is about three-quarters of a mile broad, and very deep, with a rapid current; the water being uncommonly pure. About 5 miles below, it divides into two channels, the main branch being on the west side, and between them they embody several islands, the chief one being Grand Island, which contains upwards of 17,000 acres. Below this is Navy Island, where the streams again unite and form a spacious bay about 2 miles broad, opposite to the village of Chippeway. The river now approaches one of the grandest scenes in the world, THE Below Chippeway, about a mile, the river contracts to the breadth of about a mile, and towards the fall there is a small island which separates the stream into two parts, the great volume, however, being the western, on the Canada side. Before reaching the main fall, the rapids commence, and continue for about half a mile, during which the fall is estimated at about 50 feet. The river, being about a mile broad, and very deep, presents an appearance awfully grand, which is augmented at its lower extremity by the main fall, which precipitates the whole mass of waters from the Table Rock into a cavity above 170 feet deep, by a perpendicular pitch. The water now runs in a chasm of the earth, which it has cut for itself during the lapse of ages, for 9 miles, in which the fall is estimated at 100 feet; when the ground falling by an almost perpendicular descent to nearly the level of the water, the river assumes a placid appearance between Lewistown and Queenstown, which it continues to Lake Ontario, distant 6 miles. This being one of the best positions on this most extraordinary river for forming an estimate of its magnitude, the following observations were made. The river is here about half a mile broad, it averages about 25 feet deep, and its current may be estimated Of at about 3 miles an hour. In one hour therefore it will discharge a column of water 3 miles long, half a mile wide, and 25 feet deep, which will contain 1,111,440,000 cubic feet; being 18,524,000 cubic feet, or 113,510,000 gallons of water each minute. The water passes into Lake Ontario over two bars; the water on the inner bar being about 18 feet, and on the outer about 24 feet deep. Lake Ontario is about 180 miles long by 40 miles broad, and its square contents about 7,200 miles. Its average depth is estimated at about 80 fathoms. At the east end of Lake Ontario the river passes through a singular group of islands, called emphatically the 1,000 Islands. these, Grand Isle, opposite to Kingston, is the most extensive. The river here is known by the name of Catar-` aqui. From Lake Ontario to St. Regis, the distance is about 110 miles, and here the river ceases to be the boundary of the United States. From St. Regis to Montreal is about 70 miles; and from thence to Quebec is 180 miles. In all this distance the river is very interesting, and the tide flows up to near Montreal. At Quebec, the river expands itself into a spacious bay, and after passing the Island of Anticosti, distant 400 miles, it forms the Gulf of St. Lawrence, 400 miles long and 250 broad; having two passages to the Atlantic Ocean, one by the south and the other by the north end of Newfoundland, the distance between them being above 300 miles. The elevations on this river shed considerable light on the Geological structure of this continent. Lake Erie has been found by actual survey to be 560 feet above the level of the tide water of Hudson River, Lake St. Clair above Lake Erie, 560 Lake Huron above Lake St. Clair, Lake Superior above Lake Huron, 10 570 19 589 53 642 The descent of the Niagara river between Lake Onta |