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That circular hurricanes are often experienced in the Mediterranean sea can no longer admit of a doubt, and it is probable that these meteors are formed in the Atlantic, and not within the area of the internal sea, at least those of considerable diameter, if not the whole. And as the Madeiras are not exempt from their ravages, we may not unreasonably consider that their transits eastwardly, take place sometimes as low as the parallel of 30° north, after the change of route in the west. It is also indisputable that some meteors curve as low as 20° north in the Mexican Sea ; and it may be within probability to conceive, that occasionally a stray meteor shall be found directing its return course so far easterly from the point of change, as to repass over the greater Caribbees, instead of pursuing the north-easterly route along the east coast of North America.—And further, are we not justified in believing, from the transit of storms over Gibraltar, that their route has been direct to the north-east, from the meridians of the wind ward islands.

At Gibraltar these storms have been remarked for some years past as being of a rotary character; and it will be recollected that H.M.S. Tribune, was wrecked at Tarragona, to the north-eastward, in 1839, during the passage of a furious hurricane over that place. It appears also that on the 22nd of December, 1840, Barcelona was visited by another of large dimensions, as it occupied two days and three nights in its transit ! One hundred vessels were in the port, of which ten sunk, and most of the others were more or less damaged ;-three French menof-war rode out the gale. We trust that the officer who sent a report to the Minister of Marine, extended his observations to the operation of the wind, as well as to the effects produced by it. The recording of facts like these cannot fail of becoming useful in the investigation of the subject; they are connecting links to the chain of reasoning to be exercised in the discussion, and are otherwise accessary in the developement of the truth,-no apology therefore is necessary for pursuing them.

The Diario di Roma gives an account of a severe storm which was experienced at the Papal metropolis, on the 5th day of January this year. It appears, that the violence of the wind was confined to an elevation under 160 feet from the level of the sea, as at the top of the Astronomical Observatory, the air was in a state of calm, during the whole time of its continuance. This fact is curious, on account of the current of air confining itself to the surface; the phenomenon is not we believe singular, as whirlwinds are often confined to the surface of the land and sea for some time after their formation. Mr. Redfield considers that at first the operation of the hurricane does not reach to any great elevation, and Mr. Ostler is of opinion, that the gyration at times, may be above the surface of the land, whereby a vacuum is formed below, towards which the air Fushes from all sides.

Many of those storms which pass along the longitudinal extent of the Mediterranean, appear to find their way across the Black Sea also. On New Year's day a most destructive hurricane made its transit over that basin of the ocean, so proverbial for winter tempests. Eighteen Genoese, three English, and many Austrian, Sardinian, and Neapolitan vessels were lost; seven are reported to have foundered in the Bosphorus. During the night of the 4th of January this year, a furious storm raged over Naples,—two Neapolitan ships-of-war were lost, and it s stated that on the same day, an earthquake was experienced at Riggio in Sicily.

From these and other notices, it appears that the transit of meteors is not confined to the upper portion of the Atlantic, but sweep across from west to east and north-east from the lower latitudes. It appears too, that the commonly received opinion of hurricanes, not occurring nearer the equator than the ninth degree north, has been refuted in at least one instance, as recorded by Captain Smith, of H.M.S. Comus, who encountered a storm of that nature on the 17th of October, 1833, on the north coast of Darien, which lasted twelve hours, the changes of wind having been from north-west to south-west ; subsequently, Capt. Smith ascertained that the southern limb of the meteor had devastated the city of Panama, in the harbour of which the vessels were wrecked. As this storm was progressing due west, unless it was disorganized by the mountains, it must have passed into the Pacific, and probably pursued its course onwards to the China Sea.

Passing on to the Syrian coast, a few remarks may be made on the memorable storm in which H.M.S. Zebra, was stranded “high and dry," and Beyrout suffered so much damage. Not the least extraordinary circumstance attending it is, the curious fact of the sea breaking in forty-six fathoms, or 276 feet !; this is thirty-four or thirtysix fathoms more than has ever before been noticed.

As far as information is obtained from the accounts that have been published, -all deficient in the main particulars as usual, it would appear that the evening of the 1st of December was “ quite fine," with little wind, but, that during the night, the storm commenced from the south-westward, attended with rain and lightning, and ended early on the morning of the third, its duration having been about twentyfour or twenty-six hours. The changes of wind are only incidentally mentioned as having been from south-west to west, and round to N.N.W. or N.b.W.; the shifts, therefore, amounted to ten or eleven points.

There is no notice when the crisis of the gale occurred, and the direction of the wind at the time, which omission is to be regretted. It appears, however, that the meteor was moving to the E.b.S., and should this be correct, it follows that the height of the storm was from the W.b.N., and consequently, after the Bellerophon had her topsails blown away, as the wind, from what is subsequently stated in her account, appears to have then been southerly of west.

The gusts are described as the “fiercest” that the narrator "ever experienced at sea, and of much longer continuance;” nevertheless, as fresh topsails were not only bent, but the fore topsail and the mizen, set with impunity on a wind, it may be inferred that the force of the gale must have been moderate, in comparison with that of a tropical hurricane, under the pressure of which, experience has shewn, that the strongest storm-sail set transversely to the course of the wind, would not hold many seconds; and, as to the men attempting to bend a sail aloft, decidedly no such thing could be accomplished, with the force of the wind as high as twelve. During the intervals of lulls, if these lasted sufficiently long, such a feat might perhaps be performed. ENLARGED SERIES.--NO. 4.-VOL. FOR 1841.

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It may be inferred, that although violent, the hurricanes of the Mediterranean like those which pass over Great Britain, are less severe throughout, than those experienced within the tropics.

It clearly appears, that all the officers of the squadron have not yet given their minds to the study of the “ law of storms,”—rotary storms; this is evident from the expression of hope, that the wind would draw round more southerly. A kjowledge of the theory would have explained at once, that the wind must have been expected to veer round to the north-westward, as the meteors proceed from west towards the east. The propriety, therefore, of keeping the subject “alive," in the pages of the Nautical, seems sufficiently apparent. The excellent gunnery practice for killing men, (exemplified at Acre before the aerial contention,) is a necessity which forces itself (deplorably enough,) upon the admiration of the martial spirit, against the moral conviction of its barbarity. Should we then neglect the more imperative qualification for essaying to ensure the safety of men's lives? To this philanthropic end, the humble endeavours of one of your correspondents have been directed, and who may lay claim to as powerful an espril-de-corps, as can possibly attach to any of the youthful practitioners of shot and shell.–To your exertion and talent, Mr. Editor, opposed as these are by the limited space of your pages,-all seamen must feel the greatest obligation.

Upon the whole, the squadron* appears to have escaped wonderfully well on the occasion, and if seriously considered, the event may be of great service in inducing caution with respect to vessels approaching the southern shores, and Levantine portions of the Mediterranean during that season, (November to February,) when the progressive hurricane may be expected to make its transit from westward to eastward along the entire length, or to cross it obliquely.

It is now evident that something more than good seamanship is required during a hurricane,-a knowledge of the theory; and although we have heard it called an abstruse and perplexing study, we are persoaded from practice, that it does not require an intuitive genius to master it; and we can safely assure the seaman that as a study, he will find it far more inviting than some of the dry mathematical calculations which he has to pursue in his avocation ; and as in the case of the expert navigator, he will assuredly find his proficiency in it bring its own reward,-a consummation which is as attainable in the one as in the other, and this with far less compass of mind and energy of memory, when the nature of the phenomenon is clearly understood.

In a new edition of Lieutenant Raper's invaluable work, it is hoped that a chapter on “ circle sailing ” will be added.

S. J. February 10th, 1841.

Subsequent accounts inform us, that the French Algeria squadron, and merchant ships, have suffered more than the English. The Marne corvette was lost with fifty-seven of the crew, the captain, surgeon, and a midshipman. Acheron steamer missing; twenty-eight out of thirty-two merchantmen wrecked. Triton, eighty, seen in great distress,-not since heard of. The Jena and Neptune ninety, and Uranic frigate, suffered in masts, sails, and spars, and it is supposed they had put into Cagliari, in Sardinia.

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REMARKS ON THE PRESENT STATE OF OUR KNOWLEDGE RELATIVE TO

SHOOTING-STARS, and on the determination of Differences of Longitude from observation of those Meteors.By Mr. Galloway.

[From the Transactions of the Astronomical Society.) AFTER adverting to some of the earlier opinions which have been entertained on the nature of fire-balls, shooting stars, and other igneous meteors, the author remarks that no very defuite theory was formed respecting them till towards the end of the last century; for although the cosmical origin of the more remarkable bolides and fire-balls had been suspected, the shooting-stars were generally regarded as atmospherical phenomena, which were ascribed by some to electricity, and by others to the inflammation of hydrogen gas accumulated in the higher regions of the atmosphere. In 1794, Chladni published his celebrated work, in which he gave a catalogue of all the recorded observations of fire-balls : and, from a comparison of the different descriptions, inferred that these meteors have not their origin in our atmosphere, but are cosmical masses moving through the planetary spaces with velocities equal to those of the planets, which, when they encounter the earth's atmosphere, are inflamed by the resistance and friction, and become luminous, sometimes bursting into pieces, and scattering masses of stone and iron on the ground. This opinion was at first greatly ridiculed; but the repeated and even not unfrequented fall of meteoric stones, and the discovery by Howard that all of them present an almost perfect similiarity of constitution, widely different from that of any substance found on the earth, at length forced conviction even on the most sceptical. .

From the close resemblance between fire-balls and shooting-stars, and, indeed, the impossibility in many cases of distinguishing the one class of meteors from the other, Chladni was led to ascribe a cosmical origin to the latter phenomena, At this period, however, there were no observations from which precise or certain conclusions could be formed respecting the altitudes, velocities, or paths described by the shooting-stars-the elements by which the question of their existence within or beyond the atmosphere could be solved.

In the year 1798, the first series of observations for determining these points, was undertaken in Germany by Brandes and Benzenberg. Having selected a bass-line of about nine English miles in length, and stationed themselves at its extremities, they began to observe on nights previously agreed on; and when a meteor was seen, they immediately traced its apparent path on a celestial map, noting carefully the exact times of its appearance and extinction, with any other circunstances likely to assist in identifying it. The meteors observed simultaneously at both stations were in this manner recognised with considerable certainty; and the comparison of their paths on the two maps afforded data for the determination of their parallaxes and altitudes. The results were as follows:- Between the 11th of September and the 4th of November, 1798, only twenty-two corresponding observations were obtained from which the altitudes could be computed. The altitude of the lowest was about six English miles; there were seven under forty-five miles; nine between forty-five and ninety miles ; six above ninety miles; and one at an altitude of about 140 miles. There were only two observations from which the velocity could be deduced : the first gave twenty-five miles, and the second from seventeen to twenty-one miles in a second. The most remarkable result was, that at least one of the meteors moved upwards, or away from the earth. By these observations the perfect similarity between fire-balls and shooting-stars, in respect of velocity and altitude, was completely established.

Another attempt, on a more extensive scale, to determine the altitudes and velocities of shooting-stars by means of simultaneous observations, was made by Brandes in 1823, assisted by a number of associates resident in Breslaw and the neighbouring towns. The observations were continued from April to October, and during this interval about 1,800 shooting-stars were observed at the different places, out of which number ninety-eight were found which had been observed simultaneously at more than one station. The altitudes of four of these were computed to be under fifteen English miles ; of fifteen between 15 and 30 miles; of twenty-two between 30 and 45 miles; of thirty-five between 45 and 70 miles; of thirteen between 70 and 90 miles; and of eleven above 90 miles. Two of these last had an altitude of about 140 miles; one of 220 miles; one of 280; and there was one whose height was computed to exceed 460 miles. Thirty-six orbits were obtained ; in twenty-six of which the motion was downwards, in one horizontal, and in the remaining nine more or less upwards. In three cases only the observations were so complete as to furnish data for determining the velocity ; the results were respectively 23, 28, and 37 English miles in a second, the last being nearly double the velocity of the earth in its orbit. The trajectories were frequently not straight lines, but incurvated, sometimes horizontally, and sometimes vertically, and sometimes they were of a serpentine form. The predominating direction of the motion was from north-east to south-west, contrary to the motion of the earth in its orbit,-a circumstance which has been generally remarked, and which is important in respect of the physical theory of the meteors.

A similar set of observations was made in Belgium in 1824, under the direction of M. Quetelet, the results of which are published in the Annuaire de Bruxelles for 1837. M. Quetelet was chiefly solicitous to determine the velocity of meteors. He obtained six corresponding observations from which this element could be deduced, and the results varied from 10 to 25 English miles in a second. The mean of the six results gave a velocity of nearly 17 miles per second, a little less than that of the earth in its orbit.

The last set of corresponding observations referred to in the paper was made in Switzerland on the 10th of August, 1838; a circumstantial account of which is given by M. Wartmann in Quetelet's Correspondance Mathématique, for July 1839. M. Wartmann and five other observers, provided with celestial charts, stationed themselves at the observatory of Geneva ; and the corresponding observations were made by M. Reynier and an assistant at Planchettes, a village about sixty miles to the north-east of that city. In the space of seven and a half hours, the number of meteors observed by the six observers at Geneva was 381; and during five and a half hours, the number observed at Planchettes by two observers was 104. All the circumstances of the

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