they mingle with the current of the tropics, and recommence their tour from east to west.
From this it appears that the waters of the Atlantic, between the eleventh and forty-third degrees, are constantly drawn by currents into a kind of whirlpool; and if a drop of these waters be supposed to return precisely to the place from which it commenced its motion, Humboldt has calculated, from the known velocity of the current, that it would require two years and ten months to complete its circuit of three thousand eight hundred leagues.
‘A boat,’ he observes, ‘which may be supposed to receive no impulsion from the winds, would require thirteen months from the Canary Islands, to reach the coast of Caraccas, ten months to make the tour of the Gulf of Mexico and reach the Tortoise Shoals, opposite the port of Havana, while forty or fifty days might be sufficient to carry it from the straits of Florida to the bank of Newfoundland. Estimating the velocity of the water at seven or eight miles in twenty-four hours, in their progress from this bank to the coast of Africa, it would require ten or eleven months for this last distance. Such are the effects of this slow but regular motion, which agitates the waters of the ocean.’ The Gulf Stream furnished to Christopher Columbus indications of the existence of land to the west. This current had carried upon the Azores the bodies of two men of an unknown race, and pieces of bamboo of an enormous size. In latitude forty-five or fifty degrees, near Bonnet Flamand, an arm of the Gulf Stream flows from the south-west to the north-east, towards the coast of Europe. It deposits upon the coasts of Ireland and Norway, trees and fruits belonging to the torrid zone. Remains of a vessel burnt at Jamaica were found upon the coast of Scotland. It is likewise this river of the Atlantic which annually throws the fruits of the West Indies upon the shore of Norway.
The Pacific is also one of the great boundaries of the United States. By treaties with Spain and Russia our government possesses sovereignty along the Pacific ocean from latitude forty-two degrees to fifty-four degrees and forty minutes, which is equal to about eight hundred and eighty statute miles. This great ocean extends from Beering’s Straits to the antarctic circle, a distance of three thousand two hundred leagues, and from Asia and New Holland to America. It is separated from the Atlantic and Antarctic oceans only by imaginary lines. Its extreme breadth, a little north of the equator, is four thousand five hundred and fifty leagues; between South America and New Holland, latitude thirty degrees south, it is two thousand nine hundred and seventy leagues. It contains an immense number of islands spread over its surface, particularly between latitude thirty degrees north and fifty degrees south, to which modern geographers have given the general appellation of Oceanica. It was first called the South Sea by the European navigators who entered it from the north. Magellan gave it the name of Pacific, on account of the prevalence of calms which he experienced in it; but it by no means deserves the name, as it is remarkable for the fury of its storms, and the agitation of its waters. The trade-winds, which constantly blow between the tropics, render the passage from the western coast of America to Asia very short; but the return is proportionately difficult. The Portuguese were the first Europeans who entered the Pacific, which they did from the east. Balboa, in 1513, discovered it from the summit of the mountains which traverse the Isthmus of Darien. Magellan sailed across it from east to west in 1521.34
The Pacific, by its general motion, retreats from the coast of America, and flows from east to west; and this motion is very powerful in the vast and uninterrupted extent of that sea. Near Cape Corriantes, in Peru, the sea appears to flow from the land by this single cause. Ships are carried with rapidity from the port of Acapulco, in Mexico, to the Philippine Islands. But in order to return, they are obliged to go to the north of the tropics, to seek the polar current, and the variable winds. On the other side, the south polar current, finding no land to impede it, carries along with it the polar ice even to the latitude where the motion of the tropical current begins to be felt. This is the reason why, in the southern hemisphere, floating pieces of ice are met with at fifty and even at forty degrees.
In its motion towards the west, the Pacific is impeded by an immense archipelago of flats, islands, submarine mountains, and even land of considerable extent; it penetrates into this labyrinth, and there forms one current after another. The direction which the principal of these currents observe, is conformable to the general motion towards the west. But, as might be expected, the inequalities of the basin of the sea, the coasts, and the chains of submarine mountains, sometimes turn these currents toward the north or south. We may easily conceive that a strong repercussion of the waters of the ocean, in consequence of their meeting with a large mass of land, (as New South Wales,) may even produce a counter current, which will return towards the east, and which, by breaking, will also produce other currents, adverse and dangerous to navigators, and such as were encountered by Cook and La Perouse.
The Pacific Ocean is bounded on the east by Asia. Beering’s Straits connects it with the Arctic Ocean, and the line which indicates the one hundred and forty-seventh eastern meridian, arbitrarily separates it from the Indian Ocean. Geographers divide the Pacific into the northern and southern, the equator being the line of demarcation. This ocean occupies fifty millions of square miles; nearly one fourth part of the surface of the globe. It covers three times the extent of the Indian, and twice the extent of the Atlantic Ocean.
GENERAL REMARKS ON OCEANS.
The bed of the ocean is diversified by the same inequalities that are exhibited on the surface of the land. Its greatest depth that has been ascertained by experiment, is seven thousand two hundred feet. Its mean depth is a little over three thousand feet, about the same as the mean heights of the continents and islands above its surface. Parts of the sea differ in saltness, but the difference is slight. Though more bitter than that at a considerable depth, it has been ascertained that the water of the surface is less salt. Inland seas are less salt than the main ocean, on account of the large volumes of fresh water emptied into them. The coldness of the polar seas occasions a more rapid deposit of the saline substances, and renders them more salt than those of the equator. Various theories have been formed to account for the saltness of the sea; one attributes it to the existence of primitive beds of salt at its bottom, another to the corruption of vegetable and animal matter carried into it by rivers. A third theory considers the ocean as the residue of a primitive fluid, which, after depositing all the substances of which the earth is composed, retained the saline principle. Sea-water is freed from its salt only by distillation.
In the open ocean, the prevailing color is a deep greenish blue; other shades observed in the different seas seem to be owing to local causes. In shoal places the water takes a lighter hue. The luminous appearance of the sea by night is a magnificent phenomenon, that has not yet been entirely explained. The great divisions of the sea are inhabited by their peculiar fish, and frequented by peculiar species of birds. The level of the sea is, generally speaking, every where the same; though exceptions to this rule are sometimes found in land-locked bays and gulfs, where the waters become accumulated and stand higher than in the open ocean.
CHAPTER XIII.—SOIL.
EVERY variety of soil is found within the territory of the United States, and an accurate general estimate is not of course to be formed. We will first describe that portion of the country known as the Atlantic Slope. Next to the ocean are salt meadows or marshes, but little elevated above the water, towards which, their surface has a very slight inclination. They are covered with a peculiar reddish grass, from six to twelve inches in height, growing very thick, and forming with its roots a compact turf or sward, which is only cut with a sharp instrument and by considerable force. These meadows are overflowed by the salt water a few inches deep, several times every spring, and to this their peculiar character is attributed; for when the water is kept from them by dikes, the upland grasses take root, the turf loses its tenacity and crumbles, and in a few years their appearance is entirely changed. A slope of about six feet in two or three rods lies between these meadows and low water mark; this is covered with a coarse tall grass called sedge, which requires the returns of the daily tides to bring it to maturity.
Adjoining the salt meadows, and on the same level, at the farthest extent of the overflowing of the spring tides, fresh meadows immediately commence, which generally extend to