AMER'ICA, one of the four quarters of the globe; being smaller than Asia, but larger, perhaps, than both Europe and Africa taken together. It is the only one of the four main divisions of the land that is washed by all the four great oceans--the Northern, the Atlantic, the Southern,hnd thePaCific. - '''-'' ''"L` If Terra del Fuego and Greenland are included—as ought to be done on geological grounds—A.occupies about 150° of long., and about 135° of lat. Speaking generally, its extreme length may be said to be on a meridian, and its extreme breadth on a parallel —facts which, in the light of analogy, look more like a law than an accident. As the map will show, similar coincidences occur in South A.by itself; in Africa, in Europe, in Asia, and in Australia. As between Asia and A., moreover, it deserves to be noticed that the meridional semicircles, along which run their respective lengths, form, with an interval of 180°, one and the same meridional circle.
Like the old continent, A. has been divided by nature into two •peninsulas—Darien and Suez being the isthmuses, while South A. corresponds with Africa, and North A. with Asia and Europe. Even to this extent, however, the resemblance is by no means close. In the new world, the whole of the lower peninsula is to the a. of the whole of the upper one, while Asia overlaps half the latitude, and more than half the magnitude, of Africa.
Of the northern half of A., the southern section, -on account of essential differences in character and appearance, is in general contemplated by itself under the name of Cen tral A.—the most convenient limit, perhaps, being a line drawn from the mouth of Rio Bravo del Norte to the lower end of peninsular California; and this line, besides its geo graphical propriety on both coasts, has the recommendation of marking, on the nearer coast, the international boundary of the States and Mexico. Central A., it is to be observed, has a political signification as well as a physical one, comprising, in the former sense, the comparatively small states between Mexico and New Granada— Guatemala, Honduras, San Salvador, Costa Rica, and Nicaragua.
Physically, however, these three subdivisions of A. may be regarded as one, being knit together on the w. side by a backbone, as it were, of mountains, which, under various names and various aspects, stretches from the extreme s. at cape Horn to nearly the extreme n. at the mouth of the Mackenzie. To this mountain-system we shall have occasion to refer under the distinct heads of ANDES, CORDILLERAS OF CEN TRAL A., and ROCKY MOUNTAINS, restricting ourselves at present, in accordance with the general aim of this article, to shch features of the entire chain as may incidentally come under our notice in connection with earthquakes, volcanoes, climate, or hydrog raphy; and with regard to this article generally, the subject being A. as a whole, we shall, as seldom and as little as possible, anticipate details, which, even if anticipated here, must still be repeated under the respective heads of their proper localities.
In thus treating of A., we shall consider separately its earthquakes and volcanoes, its climate, its hydrography, its history-comprehending its discovery and its colonization, but excluding anything like the annals of any individual state—and, lastly, its geology, botany, and zoology.
The earthquakes and volcanoes of A. are to be found chiefly in the backbone of moun tains already mentioned. In South A. they may be said to be exclusively so found, being confined to the Andes proper, that skirt the Pacific, and to the Venezuelan spur or branch of the main range. The same remark may be applied to Central A. But in
North A., the energy which produces both classes of phenomena appears to have followed rather the coast than the continuous chain which diverges gradually from it— earthquakes being often felt in the maritime towns of upper California, and volcanoes having left their traces behind them on the islands of Alaska. The agency in question seems to have traveled from n. to s. along the coast, having exh austed itself in its more ancient seats; and this view derives support from the obvious formation of the Sandwich Islands, which are as nearly as possible parallel with the w. coast of A., between Behring's strait and the equator. On this interesting subject we quote from Sir George Simpson's Overland Journey: "The whole group appears to have been thrown up from the deep by volcanic action advancing from the n.w. t o the s.e., and increasing in force as it advanced; so that, while island rose after island, each grew at once in height and in breadth according to the intensity of the power that heaved it upwards from the waters. Thus Bird island, a barren rock taking its name from its only inhabitants, must be con sidered as the germ of the archipelago, as the first fruits of a submarine energy that was here only kindling its fires; while the other links in the chain, Kauai, Woahoo, Mowee, and Hawaii, not only differ, as I have just mentioned, at once in extent and in elevation, but also present, as they proceed, less and less evidence of antiquity in their gradually diminishing proportions of land capable of cultivation—a proof the more conclusive, inasmuch as the soil of the whole group undeniably consists of the successive gifts of years and ages and centuries. Moreover, the visible laboratories of the subterranean fire, which are scattered over the archipelago, confirm the same view; the craters are all extinct, excepting on Hawaii; and even on Hawaii, Mouna Loa, the most south-easterly of its three great safety-valves, alone bears living testimony to the creative impulse that has called the whole chain into existence, and bears it, too, only through its lateral volcano of Kilauea, which, besides itself looking to the east, appears, by the gradual advance of subsidiary outlets down its eastern declivities, to be rolling the hidden sources of its stiength—peradventure there to forge fresh islands—under the bed of the ocean.' Climate.—In comparing A. with the older continent, we must contrast not e. and w, with each other, but w, with W., and e, with c.—neither Newfoundland with England, nor British Columbia with Kamtchatka, but Kamtchatka with Newfoundland, and Eng land with British Columbia. Such a comparison shows that the difference lies not, as is often assumed, between the two continents, but between the opposite shores of either continent within itself. For instance, at Nain, in Labrador, the mean temperature is 7° F. below freezing; while at Sitka, in Alaska, it is 12' above freezing. Ths difference of 19' between the e. and w. coasts of the new world, is only a very little less than the differ ence between the e. coast of the new, and the w. coast of the old; for the temperature of Gottenburg, in Sweden, is only 21' higher than that of Nain. It is to be remarked, however, that this difference between the opposite coasts of the two continents diminishes as we proceed southwards. New York is only 7° colder than Naples; and Florida has the same temperature as Cairo.