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in some measure, to elucidate a subject which has engaged a share of your valuable attention, and which must be one of much interest to all parties concerned with our mines.-I remain, &c. &c. WILLIAM FRANCIS.-The Fourteenth Annual Report of the Royal Cornwall Polytechnic Society, 1846.

Storms in the Southern Hemisphere.

A paragraph has lately appeared in many of the English and American newspapers, stating, that a vessel called the Charles Heddle, had scudded in circles during a storm for several days. A description of this storm, with a chart of its track, shewing also the manner in which the Charles Heddle scudded in it, has now been published by Mr Piddington of Calcutta, in his Thirteenth Memoir of the Law of Storms in the Indian and China seas.

The Charles Heddle is a brig belonging to the island of Mauritius, commanded by Captain Finck, an able seaman. The brig had been originally built as a slaver, and is a very fast sailer.

A copy of the log-book of the Charles Heddle, which was in French, was sent by the master-attendant at Mauritius, Captain Royer, to Mr Piddington at Calcutta; and Mr Piddington having procured the log-books of several other vessels which encountered the same storm, has been enabled to draw up a very instructive memoir.

The Charles Heddle sailed on the 21st February 1845, from the Mauritius, on a course nearly due north. Soon afterwards the weather became thick all round. At night the sea and wind gradually increased, and the vessel began to labour greatly. At 9h 30m P.M., the wind being at the time SE., and having begun to blow very hard, the mainyard went in two in the slings. The mizen and jib were taken in, and the vessel put before the wind, scudding under her foresail, fore-top-sail, and fore-top-mast stay-sail, until daylight. Then were struck the main-top-sail yard, and the top-gallant yard. At noon the fore-sail was close reefed, and the brig

scudded to the NNW., before the wind at SSE.

She was

now within the compass of a whirlwind, which revolved like

the hands of a watch, thus,✪ being in the Southern Hemi

sphere, in latitude 16' 42" south, and longitude 57′ 45′′ east. Scudding round in this whirlwind, the wind from SSE. became south, and continued to the brig constantly veering as she sailed round and round. Thus, in the log-book it is next recorded, that she scudded north, then to NNE., next, NE.; her course changing to ENE., to east, to ESE., to SE., to SSE., and then to south, when the wind in the log-book is marked at north. The log-book goes on to shew, that the Charles Heddle's course was changed from south to SW., to WSW., to west, to WNW., to NW., and to NNW., the wind throughout being marked in the opposite quarter, as she was scudding before it, at twelve knots an hour. Thus she completed her first entire revolution round the vortex of the storm. By this time she was reduced to bare poles, for her sails had blown away. Scudding under bare poles, she continued changing her course from NNW., to north, to NNE., to NE., to ENE., and round again through all the points of the compass, to NNW.; being marked nearly throughout as running at the rate of eleven knots, and the wind always recorded as being exactly in the opposite point to the course she was scudding. In marking this second circuit, it is stated in the column of remarks, that she broached-to several times.

In this manner did the Charles Heddle make five complete circuits, wanting only four points of the compass round the vortex of a storm, by steering always before the wind. Scudding before the wind, the brig was prevented from getting out of the whirlwind as she would have done had she been steered either towards the east, the north, or the south-east. Allusion is made to this hurricane, and to circuit-sailing in storms, in papers recently published by Mr Redfield in the American Journal of Science. He says:

"In the slow progression found in storms of the eastern seas, as already noticed, not only a complete circuit of revolution, but more than one circuit might sometimes be made, in

a gale by the same vessel, in sailing round the axis of the storm; thus adding another practical demonstration of its revolving character. One such case of complete circuit-sailing I have referred to in 1836. Mr Thom, in his account of the Rodriguez storm of April 1843, has shewn, that the Robin Gray ran once and a half times round the axis of the storm from left to right, (this being in the Southern Hemi

sphere), till, being thrown on her beam ends, she was prevented from continuing her circuit. In the same storm, the Argo made part of her second circuit, scudding round in the gale in the same direction. In like manner the Margaret made a circuit and a quarter round the axis, chiefly in the heart of the gale. Several vessels, after once falling out of this hurricane, pursued their course, again overtook it, and plunged into the heart of the storm, where they suffered most serious disasters. It appears probable, and indeed certain, that nearly all the great loss and damage sustained in this hurricane might well have been avoided by a knowledge of the laws of rotation and progression in these storms.

"But the most striking case of circular sailing in a storm, is that of the Charles Heddle in a hurricane near Mauritius, in February 1845, which has been furnished me by Mr Piddington. This was a clipper-built vessel, once a slaver, and was bound from Mauritius to Muscat. It appears from the log, that in her course round and round in the gale, the wind veered five complete revolutions in 117 hours, with an average run of eleven and seven-tenths knots per hour; the whole distance thus sailed being 1373 miles, while the progression of the hurricane at this period was less than four miles an hour. The average distance from the gale's axis is estimated at about 45 miles. During this time the vessel made a good course SW. west, 354 miles only; nearly on the usual course pursued by the hurricanes near Mauritius.

"These are results obtained by Mr Piddidgton, who has already published his twelfth memoir, and who informs me that he is preparing another on this hurricane of the Charles Heddle. In his eleventh memoir he has given us an account of two

storms, which were nearly contiguous, but on opposite sides of the equator, and revolving in counter directions

each according to the laws of rotation and progression of its own polar hemisphere."

Some idea may be formed of the figure described in one of Mr Piddington's charts, of the circuits sailed over by the Charles Heddle, by taking one end of a coil of rope, and opening it out upon a deck or floor, in such a manner as to form with the rope five distinct loops. This will also shew the direction in which the brig scudded, as ropes are coiled from left to right.

Mr Piddington is of opinion, that storms do not always dilate in their progress, but, on the contrary, that they sometimes contract; and that when they contract, the squalls of wind partake of an involute direction, drawing ships which scud nearer and nearer to the vortex. Such an action as this may, he thinks, have drawn the Briton and Runnymede transports towards the same point in their storm in the Bay of Bengal.

These two transports coming from different points, the one from England, and the other from Australia, encountering the same storm, both became involved in the vortex, and were cast on one of the Andamen Islands, within a few yards of the same spot, and at the same time.-Bermuda Royal Gazette, Sept. 15, 1846.

On the Erratic Phenomena of Scandinavia, in reference to M.
Durocher's Memoir on that subject. By M. CH. MARTINS.

When M. Durocher published his first memoir on the erratic formation of Scandinavia,* I had the honour of pointing out to the Society how readily the facts observed by this traveller admit of explanation, by supposing the ancient extension of the glaciers of Sweden and Norway.† It is the same with the present, in which the author is obliged to confine himself to the relation of what he has seen, without at

* Bulletin de la Société Géologique, 2d Series, t. iii., p. 45.
† Ibid.,
p. 102.

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tempting to explain the greater part of the geological phenomena, which he mentions in connection with the hypothesis of diluvian currents.

Direction of the Striæ.

M. Durocher's new Memoir commences with an account of the direction of the striæ in the south of Scandinavia. He gives a map of these directions, in which he fills up some blanks left by MM. Seftsroem,* Boethling,† Siljestroem, and Keilhau. But these gaps are so few in number, that by uniting the three charts to which we refer, it will be easy to construct that of M. Durocher.

The general result of the author's new researches is, that the direction of the striæ are not parallel, neither in the different provinces of the peninsula, nor in any limited locality; but that they often form more or less open angles with each other, both in the same country, and in very remote provinces. MM. Siljestroem and Keilhau had previously arrived at the same result, without endeavouring to seek for an explanation of it. This M. Durocher has attempted, but, perplexed with the multiplicity of these directions, he is compelled to refer them to numerous systems, or to different groups. Thus, for example, he found that in the neighbourhood of Christiania and Lake Mioesen, the greater part of the striæ have a certain orientation. Around Areskutan, 380

* Untersuchung über die auf den Felsen Scandinaviens in bestimmter Richtung vorhandenen Furchen,- Annales de Physique de Poggendorf, t. xliii., p. 533. 1838. With a map of the direction of those striæ throughout the whole of Southern Sweden, from 56th to 61st degree of latitude.

† Ueber die diluvial Schrammen in Finnland.—Ann. de Physique de Poggendorf, t. lii., p. 641. 1841. With a map of the orientation of the striæ in Finland.

Voyages in Scandinavie de la Commission du Nord.-Geographie Physique, t. i,, p. 193. With a map of the whole of Scandinavia, and the mean direction of the striæ in Norway, drawn by M. Bravais, according to the indications of the author.

§ Reise fra Christiania til den Oestlige Deel af Christiansands stift i sommeren, 1840.-Nouveau Magasin pour les Sciences Naturelles de Christiania, t. iii., p. 169. 1841-42. With a map, shewing the orientation of the striæ in the western part of the Gulf of Christiania.

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