OCR Text |
Show 60 STEPPES AND DESERTS. son's Bay from those which seek the Gulf of Mexico. Such a dividing line is formed north of Lake Superior by the Missabay Heights, and more to the west by the "Hauteurs des Terres," in which were first discovered, in 1832, the true sources of the Missis sippi, one of the largest rivers in the world. The highest of these ranges of hills hardly attains an elevation of 1400 to 1500 (1492 to 1599 English) feet. From St. Louis, a little to the south of the junction of the l\Iissouri and the Mississippi, to the mouth of the latter river at Old French Balize, it has only a fall of 357 (380 English) feet in an itinerary distance of more than 1280 geographical miles. The surface of J~ake Superior is 580 (618 English) feet above the level of the sea, and its depth near Magdalen Island is 742 (791 English) feet; its bottom, therefore, is 162 (173 English) feet below the surface of the ocean. (Nicollet, pp. 99, 125, and 128.) ' Beltrami, who separated himself from Major Long's Expedition in 1825, boasted of having discovered the source of the Mississippi in Lake Cass. The river in the upper part of its course passes through four lakes, of which Lake Cass is the second. The uppermost is the Istaca Lake (in lat. 47° 13', and long. 95° 0'), and was first recognized as the true source of the Mississippi in the expedition of Schoolcraft and Allen in 1832. This afterwards mighty river is only 17 feet wide and 15 inches deep when it issue~ from the singular horseshoe-shaped Lake of Istaca. It was not until the scientific expedition of Nicollet, in 1836, that a clear knowledge of the localities was obtained and rendered definite by astronomically determined positions. The height of the sources of the Mississippi, viz. of the remotest af:lluent received by the Lake of Istaca from the dividing ridge, or "Hauteur de Terre," is 1575 (1680 English) feet above the level of the sea. In the immediate vicinity, and indeed on the southern slope of the same dividing ridge, is Elbow Lake, in which the smaller Red River of the north, which after many windings flows into Hudson's Bay, has its origin. The Carpathian l\Jountains present similar circumstances in the proximity and relative positions of the sources of rivers which send their w:ttcrs respectively to the Black Sea and to the Baltic. Twenty small lakes, forming narrow groups to the south and west of Lake Istaca, have received from l\f. Nicollet, the names of distinguished European astronomers, adversaries as well as friends. The map thus becomes a kind of geographi- |