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Cape Trafalgar, without ceasing, on every tide with more or less strength according as it may be spring or neap tides. They acquire their greatest strength at half tide of springs, and are more extensive than all the rest of the Strait, reaching out in a S.W. to W.S.W. direction, passing over the Aceitera and other rocky banks near it. When a lifting sea joins with these streams of current, the proximity of these places is doubly dangerous to a vessel, on which account they keep wide of the cape when entering or leaving the Strait in a heavy sea, proving the value of the mariner's adage,—" Off Cape Trafalgar pass either far inside or far outside."
Currents on the North Coast of the Strait.—Nor are these currents less constant over the Cabezos every tide, accompanied by eddies of greater or less extent according to their strength. They extend outside and across the Bajas frequently crossing the Strait and running over the banks which are off Points Malabata and Al-Boassa, a fact that has obtained for them among the pilots of the Strait the name of Streams of the Bajas. In their normal condition they are not very strong, and in a smooth sea only produce a ripple of little consequence. But in bad weather they cause considerable breaking in the sea.
Off the island of Tarifa every half tide produces its stream of current, however small its extent. The ebb runs to the S.E. and the flood to the S.W.; the stream on the ebb always being the strongest. They vanish in proportion to the distance from the place where they commence, and appear afresh.
Those which are observed off Points Fraile, Carnero, and Europa, are similar to these already described, but of less extent, and disappearing in proportion as the Mediterranean is entered.
Currents on the South Shore of the Strait.—The streams of current off Cape Espartel, Point Judios, and off Tanger, are of no great importance, but all forming at the period of half tide.
The strongest on the coast of Africa commence between Points Malabata and Al-Boassa. They appear to be the result of the current striking against the Phoenix and Jaseur Banks on each tide, extending their effect over the great bank or Bajos, which from the coast of Africa reaches over towards the Cabezos. It may be truly said that these streams meeting with those of the Cabezos are the only ones which cross the Strait, forming at every half tide a rip from North to South.
The streams of Points Cires, Leona, and Santa Catalina extend but to a short distance from the coast, but they are strong on the spring ebbs, receiving then the strength of the general current. They are never so strong on the flood.
( To be continued.)
Weather Warnings And A Great "day Auroral" Storm.
H.M.S. "Devonshire" Sheerness, February 1863.
Sir,—Although so much has occurred since my last letter to you of the 18th November to severely try any weather theory (and mine in particular, because its "warnings" are totally irrespective of any visible or sensible prognostics), I have the pleasure of appearing again in your pages, encouraged to renew, with your kind permission, the advocacy of a "weather system" which really has, thus far, stood the test of one of those severe seasons with which we are of necessity occasionally visited. The gales and tides of the last three months have exceeded in violence and height any which, during the five years of my residence in this ship, had previously come under my observation, or perhaps that of others.
The enormous correspondence which my special coast warnings since -September have caused (principally with the readers of this magazine, and from the general warning for the next half year, as published in the Standard of 1st January last) having somewhat abated, it is my duty to the public, whose curiosity has been excited and whose approbation is so flattering, to make some statement relative to what has occurred, either as calculated to substantiate or to refute my views with regard to lunar influences on weather.
Before entering upon some necessary details which cannot be otherwise than acceptable to nautical readers, it must be remembered that for three years (and since you allowed me to first announce certain opinions, which were then novel, upon the causes of atmospheric disturbance) there has been the "dead wall" of prejudice to surmount and the "solid rock" of settled opinions to perforate: that so far from the friendly tender of help having been made by men who had the power, and whose countenance would have cheered me onward to an earlier success, the "door of science" has been not only shut but slammed against me.
I should be unworthy of the kind consideration (and this is the only reception) which has been received by me from you, in having been permitted such ready access to all the nautical interests of the kingdom through your time-honoured pages, were I to omit first to return thanks for such liberality, which we always find distinguishes genuine men of science from mere pretenders. But occasion to complain no longer exists. Thanks to your appreciation of the "clear stage" and "fair play" which British sailors at all times demand and patronize, truth and integrity of purpose have in my feeble hands proved a very "crowbar;" and through hard work with it, neither "stone walls" nor "solid rock," nor bolts nor bars, could at length exclude me.
I had, moreover, a great incentive in the occasional sneer,—in the often perceptible reliance upon the convenient aphorism as to "giving rope enough," &c., and even in the ominous long silence of opponents,—as much, perhaps, as generally falls to the lot of a determined investigator. I think it right, however, in thus divesting my mind of all vexations and even regrets, to mention this, because I am about to prove to the public that mine were not mere pretensions, or .shallow, crude "suspicions." I had weighed them before I ventured to announce them in the Nautical; but, such as they are; they might have been suppressed altogether (if only through offensive anonymous annoyances alone) had I been less self-reliant.
I am at length happy to be able to record in the Nautical that the terra "Lunarist" is no longer one of reproach:—that henceforward one may speculate on the agency of the moon in causing what we call "weather" without meeting with that derisive sarcasm which, even from the. mouth of well meaning friends, could only be a pang or a regret.
When I enter upon independent professional investigations, the opinions of others concern me little; yet in the present case there is some satisfaction in believing that Admiral Fitzroy is a convert to my theory, and is now, in fact, a "Lunarist." I am not, however, aware of his having acknowledged that such is the consequence of my researches. In the next edition of his very interesting work, called his Weather Book, he will doubtless embrace with pleasure the opportunity of gratifying my very excusable vanity in having taught so distinguished an officer.
I promised, Sir, in my last letter to honestly acknowledge in your pages if it should be found that any one of my "predictions" had been unsupported by fulfilment; and specially mentioned the then approaching period of the 21st and 22nd November, against which (among others) I had extensively warned in the August preceding. Now I can only, as it were, acquaint the hare beforehand as to the time when the "hounds will be out," puss must then take her chance of the direction they may take. It is certain the hounds will not cover the face of the whole country. It is so with weather; the changes I positively predict at defined periods may develope themselves in various ways. It is enough for me at present that I can furnish these periods.
Probabilities were in favour of storm on the 22nd November; but the great atmospheric disturbance of that period was felt rather in the North Atlantic Ocean than in Europe. These changes are upon a great scale of magnitude, and affect whole continents at a time. Our proofs of such disturbance were quite as satisfactory as, and infinitely more agreeable than if the burden of the storm had passed over us. We in England and Ireland were only on the outskirts of it; but it passed westward or raged westward of us, and this is stated upon twofold authority. First, the barometer at Sheerness fell at suchperiod precisely from 30-20 to 29-72 in.; while at the West coast of Ireland the barometer at the same time went to as low as 29-52 in. The weather at Sheerness undergoing the characteristic fall of tern-perature which I mention in all my printed lists. The scud also flew. rapidly overhead, while on the earth's surface the weather Wm still and summerlike. At the same period further North, viz., at Unst, in Shetland, an intense I'rost set in on this very same "lunar day." Secondly, the newspapers informed us that a heavy gale was blowing not far West of Scilly.
If necessary I could add more, but such is enough to convince even the unwilling; perhaps, however, I may as well add that the fineness of the day of Lunar Colure was succeeded on the "second day after, according to what I always expect and for three years have called attention to, viz, on the 24th November, by a gale. A more conclusive fulfilment could not be desired. I beg your readers to distinguish between positive changes and positive gales.
The next marked day in my list was 29th November, only marked as of ordinary disturbance; yet even this was an equally well attested period of change. There, was the usual uneasy changing, shifting of the wind and the well marked depresssion of the barometer, the wind during the day flying all round the compass.
On December 6th (the next lunar day) we had the similar change of wind, &c., with fresh gale and rain.
13th and 14th (next lunar days).—Heavy gale in the channel, with driving rain. Barometer fell -46 in. Fine aurora borealis at 9h. p.m. 20th and 21st (next lunar days).—Terrific storms, with thunder, hail, &c. At 3h. p.m. of 21st velocity of wind seventy miles per hour. The greatest depression of barometer during the gale was -97 in. Extraordinary high tide on 21st. (I had for weeks beforehand warned publicly both against storm and high tide on these very days.) 26th (next lunar day).—Gale and characteristic barometric depression.
On the 1st January, 1863, the Standard, newspaper, published days of expected change up to 1st July next. Of those for January and February have already occurred the following fulfilments at Shecrness:— January 2nd.—Heavy gale, with much rain.
10th.—Moderate gale. Fall of barometer was -25 in. Lower temperature set in.
18th and 19th.—Most destructive and terrible gale, with very high tide on the 20th everywhere. From noon to 7h. p.m. of the 20th the velocity of the wind was above seventy miles an hour. Between noon of 17th and 9h. a.m. of the 18th the barometer fell '86 in.; and from 4h. 30m. of 19th to 6h. a.m. of the 20th it fell -55 in., the lowest point of borometer during the gale having been 28-87 in. (corrected for temperature and sea level). An extraordinary "luminosity" at lOh. a.m. of 20th in the N.N.W. part of the heavens.
(N.B.—So strongly did I expect this serious weather that during weeks beforehand I distributed five hundred special warnings as to 18th, 19th, and 20th, particularly cautioning against the high tide of the 20sli. I also warned through several local papers.)
30th.—Very hoavy gale. Velocity of wind at least sixty miles per hour. Fall of barometer between llh. 30m. of 29th and Hi. p.m. of 31st was '51 in.
February 6th.—Disturbance aloft, indicated by very rapid scud from westward, while on the earth's surface it was a perfect summer's day. From llh. p.m. it blew hard outside the Thames. Two "parhelia" visible in the afternoon (see Standard of 9th February). Barometer attained its maximum height at 3h. p.m., it being 3034.
N.B.—At Unst " deluge of rain; almost a hurricane from West."
13th.—Wind all round the compass on 12th. Very strong scud from westward on 13th, although little wind at. Sheerness and fine weather. During the day the wind changed from N.E., at 9h. a.m., to E.b.S., at 10h. 30m. a.m., which continued several days.
18th and 19th.—On 18th, after four cloudless days and calm weather, clouds began to form at early a.m.; by 3h. p.m. cloudy. Wind on 17th and 18th very variable; a most gorgeous sunset on the 18th.
On 19th (the actual day of lunar equinox) the change of weather was remarkable. Instead of the fine weather which set in on the 13th (the previous lunar day) the weather on the 19th totally changed, with a light wind from N.W. and a high, slightly falling, barometer. Heavy rain set in at 4h. a.m., with thick haze and continued drizzle, and a dead calm lasted all day. (Nothing could be more marked.) Sunshine returned on the 20th; barometer singularly high and steady.
The above details of each occurring "Lunar Period," &c., are given as data for comparisons to those who are closely watching my theory in different parts of England. I need not ask you, Sir, if my absolute "predictions" were justifiable, their fulfilment through the whole period having been strictly and literally indisputable. I will not condescend to call them "forecasts." since they are founded on a law which, though newly discovered and only as yet imperfectly developed, is now established and unassailable.
As regards the unusually high tides of this winter, they are the natural consequence of the moon and sun both being in perigee; the former being also at its position of new moon. In December last such happened; moreover, almost precisely at the time of Lunar Stitial Colure (within a few hours): hence the greater rise of the high December tide (irrespective of winds and local direction); and also the diminished rise in January, when the new moon in perigee fell between the corresponding Colure and the Lunar Equinox, although the atmospheric disturbance seems to have been nearly equal in each case.
Your readers will please to observe that I specially cautioned the coast, both by letters and precise advertisement, against the storms and high tides of December and January, but not against the corresponding period in the present month, because, in the first place, the sun is now, in February, rapidly receding (so to speak) from the earth, and his disturbing power is therefore rapidly diminishing, inversely as the cube of his distance; and in the second place because the new moon of the day before the Lunar Equinox of the 19th would, on the