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THE GULF STREAM.
(From Sailing Directions.)
It is not necessary to associate with oceanic currents the idea that they must of necessity, as on land, run from a higher to a lower level. So far from this being the case, some currents of the sea actually run up-hill, while others run on a level. The Gulf Stream is of the first class. In a paper read before the National Institute in 1844, I showed why the bottom of the Gulf Stream ought, theoretically, to be an inclined plane, running upwards. If the Gulf Stream be 200 fathoms deep in the Florida Pass, and but 100 fathoms off Hatteras, it is evident that the bottom would be lifted ICO fathoms within that distance; and therefore, while the bottom of the Gulf Stream runs up-hill, the top preserves the water-level, or nearly so; for its banks are of sea-water, and being in the ocean, are themselves on a water-level.
I have also, on a former occasion, pointed out the fact, that, inasmuch as the Gulf Stream is a bed of warm water, lying between banks of cold water-that as warm water is lighter than cold-therefore, the surface of the Gulf Stream ought, theoretically, to be in the shape of a double inclined plane, like the roof a house, down which we may expect to find a shallow surface or roof current, running from the middle towards either edge of the stream.
The fact that this roof-current does exist has been fully established by
officers of the navy. Thus, in lowering a boat to try a current, they found that the boat would invariably be drifted towards one side or other of the stream, while the vessel herself was drifted along in the direction of it.
This feature of the Gulf Stream throws a gleam of light upon the locus of the Gulf weed, by proving that its place
of growth cannot be on this side (west) of that stream. No Gulf weed is ever found west of the axis of the Gulf Stream; and, if we admit the top of the stream to be higher in the middle than at the edges, it would be difficult to imagine how the Gulf weed should cross it, or get from one side of it to the other.
The inference, therefore, would be, that as all the Gulf weed which is seen about this stream is on its eastern declivity, the locus of the weed must be somewhere within or near the borders of the stream, and to the east of the middle. And this idea is strengthened by the report of Captain Scott, a most intelligent ship-master, who informs me that he has seen the Gulf weed growing on the Bahama Banks.
(From a Letter to the Secretary of the Navy, 1854, given in Mrs. Corbin's Life of Maury.*)
The U. S. brig "Dolphin," lieutenant commanding O. H. Berryman, was employed last summer upon special services connected with this office.
He was directed also to carry along a line of deep-sea soundings from the shores of Newfoundland to those of Ireland. The result is highly interesting upon the question of a submarine telegraph across the Atlantic, and I therefore beg leave to make it the subject of a special report.
This line of deep-sea sounding seems to be DECISIVE of the question as to the practicability of a submarine telegraph between the two continents in so far as the bottom of the deep sea is concerned. From Newfoundland to Ireland the distance between the nearest points is about 1600 miles, and the bottom of the sea between the two places is a plateau which seems to have been placed there especially for *By permission of Mrs. Corbin.
the purpose of holding the wires of the submarine telegraph, and of keeping them out of harm's way. It is neither too deep nor too shallow; yet it is so deep that the wires but once landed will remain forever beyond the reach of the anchors of vessels, icebergs, and drifts of any kind, and so shallow, that they may be readily lodged upon the bottom.
A wire laid across from either of the above-named places on this side to the north of the Grand Banks, will rest on that beautiful plateau to which I have alluded, and where the waters of the sea appear to be as quiet and as completely at rest as it is at the bottom of a mill-pond. It is proper that the reasons should be stated for the inference that there are no perceptible currents and no abrading agents at work at the bottom of the sea upon this telegraphic plateau. I derive this inference from the study of a physical fact, which I little deemed, when I sought it, had any such bearings.
Lieutenant Berryman brought up, with "Brooke's deepsea sounding apparatus," specimens of the bottom from this plateau. I sent them to Professor Bailey, at West Point, for examination under his microscope. This he kindly undertook, and that eminent microscopist was quite as much surprised to find, as I was to learn, that all these specimens of deep-sea soundings are filled with microscopic shells. To use his own words, "not a particle of sand or gravel exists in them." These little shells therefore suggest the fact that there are no currents at the bottom of the sea whence they come; that Brooke's lead found them where they were deposited in their burial-place.
Had there been currents at the bottom, they would have swept and abraded and mingled up with these microscopic remains the débris of the bottom of the sea, such as ooze,
sand, gravel, and other matter; but not a particle of sand or gravel was found among them. Hence the inference that these depths of the sea are not disturbed by either waves or currents. Consequently, a telegraphic wire once laid there would remain as completely beyond the reach of accident as it would be if buried in air-tight cases.
HEROIC DEATH OF LIEUTENANT HERNDON. (From Maury's Report, in Mrs. Corbin's Life of Maury.*) U. S. NATIONAL OBSERVATORY, WASHINGTON, D. C., October 19th; 1857. SIR, On the 12th day of September last, at sea, the U. S. mail steamship "Central America," with the California. mails, many of the passengers and crew, and a large amount of treasure on board, foundered in a gale [off Cape Hatteras]. The law requires the vessels of this line to be commanded by officers of the Navy, and Commander William Lewis Herndon had this one. He went down with his ship, leaving a glowing example of devotion to duty, Christian conduct, and true heroism.
The "Central America," at the time of her loss, was bound from Aspinwall, viâ Havana, to New York. She had on board, as nearly as has been ascertained, about two millions in gold, and 474 passengers, besides a crew, all told, of 101 souls-total, 575.
She touched at Havana on the 7th September last, and put to sea again at nine o'clock on the morning of the 8th. The ship was apparently in good order, the time seemed propitious, and all hands were in fine health and spirits, for the prospects of a safe and speedy passage home were very cheering. The breeze was from the trade winds quarter at N. E.; but at midnight on the 9th it freshened to a gale, *By permission of Mrs. Corbin.
which continued to increase till the forenoon of Friday, September 11th, when it blew with great violence.
Up to this time the ship behaved admirably; nothing had occurred worthy of note, or in any way calculated to excite suspicions of her prowess, until the forenoon of that day, when it was discovered that she had sprung a leak. The sea was running high: the leak was so large that by 1 P. M. the water had risen high enough to extinguish the fires on one side and stop the engine. Crew and passengers worked manfully, pumping and baling all Friday afternoon and night, and when day dawned upon them the violence of the storm was still increasing. The flag was hoisted union down, that every vessel as she hove in sight might know they were in distress and wanted help.
Finally, about noon of Saturday the 12th, the gale began to abate and the sky to brighten. At about 2 P. M. the brig "Marine," Captain Burt, of Boston, bound from the West Indies to New York, heard minuteguns, and saw the steamer's signals of distress. She ran down to the sinking ship, and though very much crippled herself by the gale, promised to lay by.
The steamer's boats were ordered to be lowered-the "Marine" had none that could live in such a sea.
All the women and children were first sent to the brig, and every one arrived there in safety. Each boat made two loads to the brig, carrying in all 100 persons.
By this time night was setting in. The brig had drifted to leeward several miles away from the steamer; and was so crippled that she could not beat up to her again.
Black's (the boatswain) boat alone returned the second time. Her gallant crew had been buffeting with the storm