NOETH AMERICA. 



61 



tic and Pacific round the northern extremity of America. The most recent are those of the 

 English under Captain Parry, who in several voyages penetrated into the Arctic Sea from 

 Baffin's Bay, and passed the winter between the 70th and 80th parallels of latitude. The ice 

 hindered his advancing beyond Lon. 110° W., but the discoveries of Captains Franklin, Ross, 

 and Beechey, make it probable that there is a communication from Baffin's Bay to Behring's 

 Strait 



6. Lakes. North America contains the largest bodies of fresh water on the face of the 

 globe, and is not less remarkable for the number than the magnitude of its lakes. Slave lake, 

 lithapescow, and Great Bear lake, are large sheets of water, which discharge themselves into 

 the Arctic Ocean through Mackenzie's River. Lake Winnipeg, which is 250 miles in length 

 by 60 in breadth, pours its waters into Hudson's Bay through Nelson's River. Between the 

 United States and Canada lies a series of great lakes, communicating with each other by a 

 succession of narrow channels or rivers, and finally emptying themselves through the St. 

 Lawrence. 



The largest of these, and the largest fresh-water lake in the world, is Lake Superior, which 

 is 420 miles in length by 170 in breadth ; having a circuit of 1,500 miles, and covering an area 

 of 35,000 square miles. It discharges its waters through the river or strait of St. Mary, 50 

 miles long, into Lake Huron, which likewise receives those of Lake Michigan. Lake Michi- 

 gan is 360 miles in length, with a mean breadth of 70 miles, and covers an area of 25,000 

 square miles ; its surface is 600 feet above that of the ocean, and its mean depth 900 feet. 

 Its waters are clear and abound with fish. It discharges itself into Lake Huron through 

 the straits of Michilimackinac, 40 miles in length ; in the northwestern part of the lake is the 

 large bay, called Green Bay. The lake shores afford few good harbors in proportion to their 

 extent. Lake Huron is 280 miles in length, and 90 in breadth, exclusive of the large bay on 

 the northeastern shore, called Georgian Bay, which is about 80 miles in length by 50 in breadth. 

 An outlet, called the River St. Clair, expands, after a course of 40 miles, into a lake of the 

 same name, 24 miles in length, and 30 in breadth, which again contracts, and enters Lake Erie 

 under the name of the river Detroit, 25 miles in length. Lake Erie, the next link in this great 

 chain, is 270 miles in length by from 25 to 50 in breadth. The river Niagara, 36 miles long, 

 carries its surplus waters over a perpendicular precipice 165 feet high, into Lake Ontario, 

 which is about 190 miles in length, by 40 in breadth. The surface of Lake Superior is 625 

 feet above the level of the sea ; its medium depth 900 feet ; the descent to Lake Huron is by 

 the Sault or Fall of St. Mary, 23 feet, and by rapids and the gradual descent of the river, 21 

 feet, giving 580 feet for the elevation of the surface of Lake Huron, whose depth is equal to 

 that of Lake Superior. Lake Erie is much shallower, not exceeding a mean of 120 feet, and 

 having its surface 560 feet above high water, while Lake Ontario has a depth of 500 feet, and 

 its surface is 330 lower than that of Lake Erie. The waters of these lakes are clear and 

 potable, and they abound with fish, among which are trout, weighing from 75 to 100 pounds, 

 sturgeon, white fish, pike, bass, &c. They are navigable by large vessels, and a great number 

 of steamboats navigate their waters. 



7. Table-lands. The great Mexican table-land, upon which are situated most of the prin- 

 cipal cities, and upon which is concentrated most of the population of the Mexican States, 

 has an elevation of from 4,000 to 8,000 feet, and extends from Chihuahua in the north to the 

 state of San Salvador in Central America on the south. The Alleghanian plateau or table- 

 land, extending from New York to Alabama and Georgia, from 34° to 42° N. Lat., has an 

 elevation of from 1,200 to 3,000 feet. It comprises the western part of Pennsylvania, Vir- 

 ginia and North Carolina, the northwestern part of South Carolina and Georgia, the northern 

 part of Alabama, and the eastern part of Tennessee and Kentucky. The Central Table-land 

 of North America, which comprises the region containing the sources of the Mackenzie, the 

 Saskashawan, the Columbia, the Missouri, the Mississippi, the Western Colorado, and the 

 Rio del Norte, is from 2,300 to 3,500 feet high. 



8. Plain. The vast plain, which extends entirely across the continent from the mouth of 

 the Mackenzie to the Delta of the Mississippi, and spreads out between the Rocky and the 

 Appalachian Mountains, is the largest in the world, having an area of 3,250,000 square miles. 

 It embraces the valleys of the Mackenzie, the Saskashawan, the Missouri, the St. Lawrence, 

 and the Mississippi, and stretches from regions of perpetual ice to the tropical climate of the 

 Gulf of Mexico. It is in this plain that the traveller meets those wide expanses, called 

 prairies, over which the eye wanders, as over a sea, tih the vision is lost in the distance, and 



