THE TROPICAL OCEAN.
Wanderings of an Iceberg—The Tropical Ocean—The Cachalot—The Frigate Bird—The Tropic Bird—The Esculent Swallow—The Flying-fish—The Bonito—The White Shark—Tropical Fishes—Crustaceans—Land Crabs—Molluscs—Jelly Fish—Coral Islands.
Day after day the glacier of the north protrudes its mass farther and farther into the sea, until finally, rent by the tides, and with a crash louder than that of the avalanche, the iceberg rolls into the abyss. The frost-bound waters, that have languished so many years in their Greenland prison, are now drifting to the south, on their way to the tropical ocean; but the sun must rise and set for many a day before they bid adieu to the fogs of the north.
See there yon dismal ice-blocked shore, with the jagged mountains in the background, their snowy peaks rising high into the sky. Screeching sea-birds—fulmars, gulls, guillemots, auks—mix their hoarse voices with the melancholy tones of the breakers and the winds, and between them all resounds, from time to time, the bellowing of the walrus or the roar of the polar bear.
The weak rays of the sun, just dipping over the horizon, have called forth these symptoms of life; but as soon as the267 great luminary disappears, animal creation becomes mute, and the voices of the air and ocean are again the only sounds which break the silence of the arctic night.
The crystal mass floats along, buried in deep darkness; but soon a new and wondrous sight is seen, for the flaming swords of the northern light flit through the heavens, casting a magic gleam, here on the desert shore, there on the dark bosom of the sea.
Advancing farther and farther to the south, the iceberg loses one after another the witnesses of its first migrations, and wasting more and more, at length entirely merges in the tepid Gulf Stream. The enthralled waters are now all liberated, but many on their western passage are again diverted to the north, and the others reach, only after a long circuit, the mighty equatorial stream, which carries them along, through the torrid ocean, from one hemisphere to the other.
SPERM WHALE.
The animal life they meet with in these sunny regions is very different from that which witnessed their passage through the higher latitudes.
The large whalebone whale, the rorqual and narwhal of the north, have disappeared, but pods of the mighty sperm whale rapidly traverse the equatorial seas.
The birds also exhibit new types of being. The royal albatross avoids the torrid zone, but the high-soaring frigate-bird hovers over the waters, where it is seen darting upon the flying-fish, and, like the skua gull of the north, attacking the weaker sea-birds in order to make them disgorge their prey.
FRIGATE BIRD.
268 ‘He is almost always a constant attendant upon our fishermen,’ says Dr. Chamberlain,24 ‘when pursuing their vocation on the sand-banks in Kingston Harbour, or near the Palisados. Over their heads it takes its aërial stand, and watches their motions with a patience and a perseverance the most exemplary. It is upon these occasions that the pelicans, the gulls, and other sea-birds become its associates and companions. These are also found watching with equal eagerness and anxiety the issue of the fishermen’s progress, attracted to the spot by the sea of living objects immediately beneath them. And then it is, when these men are making their last haul, and the finny tribe are fluttering and panting for life, that this voracious bird exhibits his fierce propensities. His hungry companions have scarcely secured their prey by the side of the fishermen’s canoes, when, with the lightning’s dart, they are pounced upon with such violence that, to escape his rapacious assaults they readily, in turn, yield their hard-earned booty to this formidable opponent. The lightness of its trunk, the short torso and vast spread of wing, together with its long slender and forked tail, all conspire to give it a superiority over its tribe, not only in length and rapidity of flight, but also in the power of maintaining itself, on outspread pinions, in the regions of its aërial habitations amidst the clouds; where, at times, so lofty are its soarings, that its figure becomes almost invisible to the spectator in this nether world.’
The beautiful tropic birds, whose name implies the limit of their abode—for they are seldom seen but a few degrees south or north of either tropic—hover at such a distance from the nearest land that it is still an enigma where they pass the night—whether they sleep upon the waters, or whether their extraordinary length of wing bears them to some isolated rock. Nothing can be more graceful than their flight. They glide along, most frequently without any motion of their outstretched pinions, but at times this smooth progression is interrupted by sudden jerks. When they see a ship, they never fail to sail round it, and the mariner bound to the equatorial regions hails269 them as the harbingers of the tropics. The two long straight narrow feathers of which their tail consists, are employed by the natives of the greater part of the South Sea Islands as ornaments of dress, and serve to distinguish the chieftains from the multitude.
The esculent swallow (Colocalia esculenta)—whose edible nest, formed by a secretion which hardens in the air, is one of the greatest dainties of the Chinese epicure—may almost be considered as a sea-bird, as it chiefly inhabits marine caves in various islands of the Indian Archipelago, and exclusively seeks its food in the teeming waters.
ESCULENT SWALLOWS’ NESTS.
The steep sea-walls along the south coast of Java are clothed to the very brink with luxuriant woods, and screw-pines strike everywhere their roots into their sides or look down from the margin of the rock upon the sea below. The surf of ages has worn deep caves into the chalk cliffs, and here the swallow builds her nest. When the sea is most agitated, whole swarms are seen flying about, and purposely seeking the thickest wave-foam, where no doubt they find270 their food. From a projecting cape, or looking down upon the play of waters, may be seen the mouth of the cave of Gua Rongkop, sometimes completely hidden under the waves, and then again opening its black recesses, into which the swallows vanish, or from which they dart forth with the rapidity of lightning. While at some distance from the coast the blue ocean sleeps in peace, it never ceases to fret and foam against the foot of these mural rocks, where the most beautiful rainbows glisten in the rising vapour.
Who can explain the instinct which prompts the birds to glue their nests to the high dark vaults of those apparently inaccessible caverns? Did they expect to find them a safe retreat from the persecutions of man? Then surely their hopes were vain, for where is the refuge to which his insatiable cupidity cannot find the way? At the cavern of Gua Gede the brink of the coast lies eighty feet above the level of the sea at ebb-tide. The wall first bends inwards, and then at a height of twenty-five feet from the sea throws out a projecting ledge, which is of great use to the nest-gatherers, serving as a support for a rattan ladder let down from the cliff. The roof of the cavern’s mouth lies only ten feet above the sea, which even at ebb-tide completely covers the floor of the cave, while at flood-tide the opening of the vast grotto is entirely closed by every wave that rolls against it. To penetrate into the interior is thus only possible at low water, and during very tranquil weather, and even then it could not be done if the roof were not perforated and jagged in every direction.
The boldest and strongest of the nest-gatherers wedges himself firmly in the hollows, or clings to the projecting stones while he fastens rattan ropes to them, which then hang four or five feet from the roof. To the lower end of these ropes long rattan cables are attached, so that the whole forms a kind of suspension bridge, throughout the entire length of the cavern, alternately rising and falling with its inequalities. The cave is 100 feet broad and 150 feet long, as far as its deepest recesses. If we justly admire the intrepidity of the St. Kildans, who, let down by a rope from the high level of their rocky birthplace, remain su............