As the travellers proceeded almost due north the island of Great Bahama soon came to form the eastern boundary of the Gulf Stream. In this locality many fearful storms have occurred, for when the river is angry it is one of the most fearful places in the world for a ship to be. It is said that the whole of the Bahama Islands which lie scattered through the sea to the east of the Gulf Stream rest on a foundation of submarine banks formed by the deposits of the river. The same may be said of the islands which line the coasts of Georgia and the Carolinas on the west. Off one of these islands the captain distinctly made out the wreck of a large craft, floating free on the edge of this current, which he has since been told was the City of Savannah, wrecked in the great storms of 1893. Derelicts are common in these parts, no fewer than forty having been reported last year.
Long ago the soundings taken by the officers of the American Coast Survey showed, according to Lieut. Maury, that the Gulf Stream flows along the coast of America at some distance from the land. The slight inclination of the low lands of Georgia and Carolina is continued under water till the sounding line attains a depth of about fifty fathoms. The bottom then sinks rapidly and forms a long valley parallel to the shore of America and the chalky walls of the Appalachian range. In this valley, hollowed to the east of the submarine basement of America, the Gulf Stream waters flow. Owing to the rotatory motion of the globe and also to the curve of the coasts, the Stream follows a constant direction to the north-east. Off New York and Cape Cod it deviates more and more to the east. It ceases to follow the coast-line, and rolls across the open Atlantic towards the shores of Western Europe. Thus, as Maury says, if an enormous cannon had force enough to send a bullet from the Strait of the Bahamas to the North Pole the projectile would follow almost exactly the curve of the Gulf Stream and, gradually deviating on its way, reach Europe from the west.
THE SOUTH SHOAL LIGHTSHIP, WHICH MARKS THE SITE OF AN OCEAN GRAVEYARD.
We have spoken of the driftwood boundaries of the Gulf Stream; but there is an even more pronounced barrier easily ascertained by a use of the thermometer. The warmest and most rapid part of the Gulf Stream is that in most immediate juxtaposition to a sheet of cold water flowing in an opposite direction off Carolina which bounds our river like a wall of ice. Occasionally the line of demarcation is so precise that it is visible to the naked eye, and the exact moment when a ship leaves the cold current and its prow cleaves the Gulf Stream may be observed. The latter waters are of a beautiful azure, that of the counter-current is greenish; one is saturated with salt, the other contains the mineral to a far slighter extent. But the chief distinction is that one is tepid, the other frigid as ice.
On the 21st one of the men reported having sighted a light to the north, and had also clearly heard a distant bell tolling. This was probably the South Shoal Lightship, which marks the site of an ocean graveyard hereabouts. This lightship, with a crew of a dozen men, has been adrift nearly thirty times in the course of her history, and was once fourteen days in the Gulf Stream. She is a schooner or barge of two hundred and seventy-five tons, about one hundred feet long, chained to an anchor of three and a half tons. But it is said the life aboard is so unbearably monotonous to the crew that they cut the chain and so send the lightship adrift. The skipper was glad when the Gulf Stream carried him away from the neighbourhood, for he was reminded that over five hundred wrecks have taken place some leagues to the northward of his course.
"THE TEMPERATURE OF THE STREAM WAS DISAGREEABLE TO HIM."
The Miosen was now bound almost due east, as if headed for the Azores, for the great river curves at this point. Just south of Halifax, in longitude sixty-five degrees, they came across their first iceberg, drifting on the very edge of the stream. There is nothing so unhealthy for an iceberg as the Gulf Stream, and an iceberg seems to know it. When, however, it is fairly caught in its clutches it soon melts away to nothingness before it has been carried many leagues eastward, all depending, of course, upon its size. As with icebergs, so with whales, as we have already mentioned. The vessel encountered a whale later in longitude fifty, but it was obvious that the temperature of the Stream was disagreeable to him, for he soon headed again for the Arctic regions. Other whales make a dash through or remain by the side of the big river and so reach lower latitudes, but a brief sojourn is enough for them. The Gulf Stream is a river which can boast everything maritime but whales.
The great river just touches the southern extremity of the Grand Banks of Newfoundland. This bank of Newfoundland, an enormous plateau surrounded on all sides by abysses five to six miles deep, is chiefly due to the contact of the Arctic current with the Gulf Stream. For here is the chief graveyard of icebergs. On entering the tepid waters of the river the frozen mountains gradually melt and let fall the fragments of rock and loads of earth they bear into the sea. The bank, which rises gradually from the bottom, is the work of the Greenland glaciers and the floes of the Polar Sea. It is the presence of the Gulf Stream in these latitudes which is the cause of the prevalent fogs not only here, but in the islands off Europe. From here onward a sailor can always tell whether or not he is in the Stream by plunging a thermometer overboard. Capt. Westrup found that it crosses the Atlantic with a mean speed of twenty-four knots a day. This had previously been ascertained, according to Maury, by direct measurement at different parts of the ocean, or by means of notes, which, having been thrown overboard in bottles, carefully closed, have floated for weeks or months at the will of the waves, and then been fished up in other latitudes or found on some seashore. In its long journey this mighty river transports hardly any other alluvium than the living frustules of animalculæ which fill the tepid waters of the current, and are constantly falling like snowflakes to the bottom of the ocean. However, during the whole distance across the Miosen constantly met with the trunks and branches of trees, cane stalks, and woody flotsam, much of which finally reaches the coasts of Europe, even as far as Spitzbergen.