The practical, value of the enterprise of connecting by navigation the Pacific and Atlantic oceans is already evidenced by the fact, that, in the face of the competition of the last two routes, the Panama railroad is perhaps the most profitable undertaking of the kind in the new world. In fact, the completion of any one of these three routes for sea-going ships, would be to realize Columbus's idea of a western passage to the east.
Of the lades of A. a brief notice will be sufficient. In North A., besides the vast reser voirs of the St. Lawrence, a line drawn n.w. from the center of lake Superior appears, on the face of the map, to intersect a kindred series—lake Winipeg, lake Athabasca, Great Slave lake, and Great Bear lake—the first of the four being connected with the Nelson, and the remaining three with the Mackenzie. It may not be out of place to observe, that the general direction indicated is pretty nearly parallel with the Pacific coast, just as the general direction of the St. Lawrence from the great bend at time head of lake Eric is pretty nearly parallel with the Atlantic shores. As to the secondary lakes of n.w. A., their name is legion, almost every stream, whether large or small, expanding itself here and there vastly beyond its average width, and being, as it were, a St. Lawrence in miniature. One lake, or rather pond, is too singular to be overlooked. On the Atha basca pass of the Rocky Mountains, where the road, little better than a succession of glaciers, runs through a region of perpetual snow, a small body of water, named by the Hudson's Bay Company's voyageurs as the "Committee's Punch-bowl," sends its tribute from one end to the Columbia, and from the other to the Mackenzie. To proceed south wards along the continent, Central A. abounds in lakes. The Leon and the Nicaragua have been already noticed. But such bodies of water are perhaps most ntunerous on the table-laud of Mexico, or as it is often termed, the plateau of Anahuac. The largest of these is Chapala, estimated to contain 1300 sq.m.—an area, which, however insignificant in comparison with the great lakes of the n., is more than equivalent to a circle of 40m. in diameter. Many of these reservoirs of the table-land have no outlet. Such is the case with the various lakes of the valley of Mexico, inclosed as they are by mountains at a height of 7471 ft, above the sea-level. Of the siune deseriptiou, too,,is the lake of Titi erica, decidedly the largest in South A. Raised by the table-land of Peru and Bolivia
to a height of 12,846 ft., it yet has no outlet to the sea; for the Desaguadero, which empties it, loses itself in the apparently landlocked lake Uros to the southward. Of this great body of water, the magnitude is not so well ascertained as its altitude. Besides such round numbers as 16,000 and 5000 sq.m., which are never meant to be accurate, one is perplexed to meet. statements so minute, and yet so discordant, as 4032 and 2225 square miles. But even the lowest estimate is more than equivalent to a square of 47 in. a side —an area which, with a depth ranging up to 120 fathoms, exceeds, perhaps, anything to be found to the s. of the basin of the St. Lawrence.
The vast advantage in point of fluvial communication possessed by the new world over the old, has already been adverted to. There is, however, a hydrographical feature in which one of the grand divisions of the eastern continent is decidedly superior to A. The coast-line of Europe, in proportion to extent of 'surface, is incomparably longer than that of even the northern half of the western continent. This is at once apparent on glanc ing at the two maps. It is surely a suggestive fact that the two portions of the earth which are best fitted for human intercourse are also hydrographically so connected as to be beyond comparison the most accessible to each other. The dividing sea, besides being itself physically by far the narrower of the two intercontinental oceans, is virtu ally narrowed still more by its winds and its currents. Along a belt of about 30° on either side of the equator, the easterly trade with its attendant current wafts the voyager westward from Africa; while above that belt the reaction, strengthened and accelerated by the peculiar formation of the Caribbean sea and the gulf of Mexico, is ready to carry him round again to Europe, under the double pressure of the Florida stream and its generally prevailing breezes from the south-west. Nor yet can the hydrographical rela tions of A. with Asia be denied their proportion of significance and influence, linked as the two continents are by strait, and twice bridged as is their ocean, first by the Aleutian isles—a continuation of the Kuriles and Japan—and then by the Polynesian clusters, that series of offshoots, as it were, from the Indian archipelago.