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ship off to pass it on the gulf or western side. But the light proved to be the new one on Sombrero Shoal (just opposite), of which the captain had no notice, and she struck a shoal inside the main reef. A glance at the chart will show how far these captains were mistaken in their estimate of both the force and direction of the current.
“Some years since a fishing smack left Key West to go to Cape Florida. The wind was eastwardly, and after she had beaten to windward for some forty-eight hours, she stood in to make the land. She fetched twenty miles to the westward of the starting point, showing in this instance, a strong westerly current from the centre of the Gulf.”
Mr. Tift adds that he “knows that the 'gulf current sometimes, though rarely, runs strong to the eastward a mile or more inside of the reef (at Key West), but that the general set is westward for a short distance from the main reef." The idea, however, of a “strong westerly current” on this “edge," must be taken with many grains of allowance. A ship-master leaving the strong gulf current and approaching the margin, finds the set so reduced in its rapidity as to conclude that he has found the stream actually going westward. As stated above, this is only true to a very limited extent, or in other words the belt of westwardly current is very narrow.
I am indebted to Mr. Baldwin, collector at Key West, for a case in his own experience showing a westerly drift, and for some observations made specially valuable by his long and full acquaintance, not only with the matters in question, but with the navigators frequenting Key West.
In June, a few years since, Mr. B. made a passage in a fastsailing brig from Mexico to Havana. After leaving Campeachy Bank, they made Tortugas Islands and took a departure about sunset, steering about southeast by east. About midnight it fell calm, and for five days they experienced only calms and occasional light airs from the south. On the sixth day there was a light wind from the east. The master, an experienced navigator and well acquainted with those waters, steered south, supposing he had drifted through the Gulf. On the morning of the seventh day he made land, which he supposed was somewhere near Matanzas, but which turned out to be near the Colorados, a reef off the west end of Cuba.
Again, in a voyage from St. Marks to Key West, Mr. Baldwin says, that being set by strong southwest currents in the Bay of Mexico, they fell to leeward and made the Tortugas Islands. Having an experienced pilot they ran through into the gulf between the Tortugas and the Quicksands. After beating to wind. ward for three days they stood in, and found themselves six miles to leeward of where they entered the gulf. Satisfied that
down obser Gulf Stres to the nee at Keyche no
they had to contend with a strong westerly current, the master consented to beat up inside the reef, and they reached Key West in thirty-six hours.
Mr. Baldwin says he has conversed with many intelligent ship-masters, with the Key West pilots, and with the masters of fishing smacks who are constantly crossing and recrossing the gulf to and from Cuba, and says that they assure him that no dependence can be placed on the Gulf Stream; sometimes it runs very much stronger than at other times in a northeast direction: that it very frequently runs in a southwest direction; and that at other times there is no current at all. Very frequently they experience an easterly current on the Cuba coast and the reverse on the Florida coast, and at other times a strong current in the centre. The current cannot be mistaken, as the change is perceptible to the eye.
Mr. Baldwin adds, " A great deal depends on the force of the wind. My own observation has satisfied me that the wind infiuences the set of the Gulf Stream; for instance, after a heavy northeast wind the stream sets to the northeast at a very rapid rate, and vice versa. Since my residence at Key West, I have known several vessels to be brought in from the northwest, having got into the Bay of Mexico, when supposing themselves east of Cape Florida.”
He was assured by the master of a vessel from Honduras, and another from Central America, both stranded, that they had come round Cape Antonio, and after beating as they supposed in the gulf, aided by the Gulf Stream for a number of days, discovered land, and judging it to be the Bahamas, shaped their course through the gulf, and were stranded near the Cedar Keys.
These scraps of testimony might be much extended if necessary, but I suppose they fully suffice to show that we are still very far from possessing the knowledge the case demands. They clearly prove that there is enough westerly current in the Gulf of Florida to be of vast importance to navigation if its movements can be defined, and to constitute a great danger, if it is not known. Its variations are also well established, and should be known to navigators. I am also quite well persuaded, not only from actual testimonies, but from the fact that a coral bank extends above Cape Catoche, that at least a large part of the Gulf Stream turns to the northeast around the west end of Cuba, instead of making the circuit of the Gulf of Mexico. The effect of the earth's rotation, and of its own inertia, on the current coming north from the Caribbean Sea, would be to give it an eastward bend. It is also quite incompatible with the tendency of the westerly current to expand towards Tortugas, to · suppose that the main Gulf Stream comes sweeping in from near the mouth of the Misissippi towards this point.
cum varioula iveta cely
Before attempting to theorize on the cause of this westerly current, it is certainly very desirable that it should be more accurately defined. The effect of dragging by the Gulf Stream along its sides, may perhaps be to produce a deficiency of water behind, to be replaced by a return current of this degree of force, but it would certainly not call for such a vast body of westerly current as is vouched for in some cases, nor would it explain its alleged fluctuations. Some of the wrecks which have lately occurred seem due to a strong current setting through the Santarem Channel, and we may see in this a suggestion of a cause for the westward currents when these exceed the magnitude of a proper eddy. A Santarem current projected across the gulf, may be thrown down the reef, though I should not much expect such a result.
It will be well here to call attention to the refutation of the theory that the Gulf Stream owes its progress to a declivity resulting from heaping up waters in the Gulf of Mexico, which this parallel counter current affords. There is no evidence of any such elevation of the Gulf of Mexico as this theory calls for. On the contrary there is no such southeast current across from the Bay of Mexico, Barnes's Sound, &c.,-as such an eleva. tion would inevitably create. The whole motion of a descending river in the sea, with its source in the Gulf of Mexico, seems to me quite untenable and conflicting with facts.
The natural conclusion from what has preceded is, that there is abundant need of further exploration into the movements of this whole system of currents. Their incalculable commercial importance makes such an inquiry any thing but speculative, and should stimulate active and well-conditioned observations. We well know how imperfect the observations by the drift of ships must be; they are rather indications than measurements.
In view of the present state of the case, I would ask attention to the promise of results offered by undertaking an extensive series of current bottle observations; on the line from Cape St. Antonio to Cape Catoche. By systematic proceedings several points might be well illustrated. Suppose a vessel to cross on this line, say twice monthly for a year, throwing over one or two hundred bottles each time, containing slips duly numbered so as to indicate each starting point accurately; these points being regularly distributed on the line run, and checked by the verification of the route sailed. As these bottles proceed on their course, they will become faithful witnesses of the currents, and by their spreading they will show conclusively what the real course of the Gulf Stream is, and whether it is broken, one branch sweeping around the gulf coast, and the other pushing
SECOND SERIES, VOL. XXVII, No. 80. -MARCH, 1852
on northeasterly. With a view to promote their being readily picked up at sea, I would propose that flasks of white glass, blown with broad bases, should be used. These could be seen at a distance, and in a region so crowded with sails as the Gulf of Florida, very many would be picked up while still afloat, thus giving a true measure of mean velocity. A small sailing vessel, such as one of the Key West pilot boats, or the revenue cutter at that station, might, by having a good observer put aboard, make such a course of observations with slight expense in proportion to the results. It is hardly needful that I should here further state the bearings of such a plan, but I think all will concede to it the promise of elucidating some important questions of the Gulf currents. It would surely be much better, could deep sea observations be made also, and to some extent probably they might be connected with a current bottle campaign. The superficial study, ought certainly not to be longer deferred; after this, we can take a next step more wisely.
ART. XXVI.—Abstract of a Meteorological Journal, kept at Marietta,
Ohio: lat. 39o.25 N. and lon. 4°.28 W. of Washington City; by S. P. HILDRETH, M.D.
Temperature.— The mean temperature of the year 1858 is 53°:75; more than two degrees above that of 1857, which was 51°.43. The extremes of heat and cold have not been so great as in some years, especially that of cold; the lowest grade of
the thermometer being only five degrees below zero, in February.
Rain and melted snow.—The amount of rain and melted snow is sixty-one inches and eighty-four hundredths, a quantity somewhat exceeding that of any other year since I have kept a reg. ister, thirty-two years, and with that kept by Mr. Wood from 1818, making forty years; forty-two inches is the mean amount for a series of years, but in dry periods it sinks sometimes to thirty-two inches, about half that of the past year. The month of May exceeded in quantity that of any other, being nearly twelve and a half inches. It was divided among the seasons as follows: winter 1370 inches, spring 1842 inches, summer 1518 inches, autumn 13% inches. The quantity of snow was small, four inches being the greatest depth at any one time, not affording sufficient for sleighing.
Winter.—The winter of 1858, was uncommonly mild, the mean being 36°:54; more than six degrees above that of 1857, which was 30°:35; while that of 1856. was 25°:50, the lowest of any one on record. The moderate weather continued until near the middle of February, about which time the Ohio river was open and navigable for steamboats. The mean for December was 41°20, and that of January 40°•44, being many degrees above that mean for these months, so mild was the weather that it was feared we should have no ice for summer use. The buds of fruit trees swelled as they do in March, and some peach trees on a high sandy ridge of land in Noble county, fifteen or twenty miles north of Marietta, opened their blossoms on the 28th day of January, and what is very curious, notwithstanding the cold in February and March, produced fruit. It was as late as the 18th of February before navigation was closed by ice, and the 24th before the Ohio was frozen over. It remained shut only a few days, and boats were again running by the tenth of March. In a majority of years, the Ohio is closed for a short time in De. cember, but invariably opens again at or near the winter solstice, when there is commonly an abundance of rain. February was a cold month, the mean being 28°.00; whereas in 1857 it was 42°-73, a difference of nearly fifteen degrees. The earlier part of the winter was mild all over the valley of the Ohio.
Spring.–The mean temperature of the spring months is 520.03; being nearly seven degrees above that of 1857, and a full medium for this climate, the difference being occasioned by the higher temperature of April. The mean of this month is con. sidered as usually representing that of the year, but in 1858 was nearly three degrees above it. The month of May was about the ordinary temperature 60°:70. The early part of March was uncommonly cold, the mercury falling to zero on the seventh of