cliffs with a dark wood in the rear, show very conspicuously. The cape may be rounded to within two cables' length if required. The coast from Dipper Harbour to the westward has red cliffs, to the eastward they are white; this is an excellent guide to strangers; five miles east of Cape Lepreau we first raised the land of Passamaquoddy.

The back land of Maces Bay is high, and Red Head, its western point, is particularly well marked. Over Beaver Harbour the land is still higher, and makes in saddles or notches. From Musquash Harbour, a W. by S. to W. by S. S. course will lead clear and between the Wolves and Grand Manan, the north end of which being a bold bluff point, may be rounded very close. The distance from Cape Lepreau to Machias is forty miles. At seven P.M. we were clear of Machias Seal Island, and steering away for Bermuda. This lasted but for a short time; we had scarcely made twenty miles before the wind went round to the southward, and blew a gale right up the bay with a tumbling sea. We lay to until four P.M. of the following day, (28th,) when a north-wester sent us scudding along rather faster than we 'could have wished. Six P.M. of 29th, in latitude 41° north, and longitude 65° 33′ west, the thermometer gave air 34°, water 58°; this was on the north edge of the gulf stream; barometer had fallen to 29.16. Heavy gale with snow storms; high cross swell; pitchy dark night; scudding at a fearful rate; ship lurching heavily with forward plunges; at ten the lee quarter boat was washed away, and at two, in the middle watch, lost the small bower anchor; it was well stowed, lashed, and secured; the giving way of the bolt for the standing part of the cat-head stopper, was the cause of this loss. This was a very heavy gale, and the storms of snow and sleet heavy and frequent; the last snow storm was in latitude 36° north; it drove past the ship thick and fast, coating the weather side of the cordage, masts, yards, &c. its contrast with the paint and tar gave the whole a singular appearance; heavy dense masses of cloud moving rapidly, driving over the mast-heads, and settling to leeward in one impervious mass.

The previous night I witnessed, for the first time, several luminous meteors, which are seen, like the ignis-fatuus, flitting as fast as the eye can follow. Seven were observed at one time at the mast-heads, yard-arms, &c.; they were seldom stationary, and appeared particularly brilliant during the raging of a squall. During the day we noticed a vapour passing over the sea, very close, like veins of a partial fog; this no doubt was caused by the great difference in temperature between the air and water, it being 24° throughout. I have before mentioned the difficulty in defining the southern edge of the gulf stream; in the present case, to within 150 miles of Bermuda the water continued 14° warmer than the air. We may, therefore, consider that the north-west storm of three days had driven the body of the stream far to the southward, and that at daylight, this morning, 31st, in latitude 37°, we crossed its southern edge, the thermometer at

that time showing air 46°, water 66°; and four hours later it gave air 51°, water 65°. While in the stream the current set to the southeast, one mile per hour. The weather cleared up on the 31st, and on the 2nd February, we anchored at Bermuda. Cornwallis told the tale of her having been tempest-tossed; indeed, she exhibited the appearance of a battered old wreck.

23rd February.-Sailed with the Admiral to Jamaica, Havana, and back. In passing Alto Vela, with the chronometers just rated, fine clear morning, the rock bearing north quarter west, ten miles, the longitude was 71° 41' 47" west. The correctness of this was ascertained three days after by sights taken at Fort Charles, Port Royal. We returned

to Bermuda on the 10th April, and having embarked the 11th regiment, sailed again for Halifax on the 14th. This regiment will make 2,000 men, women, and children, who have embarked since December. Again anchored at Bermuda, on the 3rd May.

HENRY DAVY.

SUNKEN ROCK IN THE PORT OF HERRADURA.-Coast of South America, Pacific.

EXTRACT of a letter from Mr. W. H. Lamotte, commander of the barque Morayshire, dated Valparaiso, Jan. 16:

"I wrote to you by the Persian, informing you of the unfortunate accident I met with in going into the port of Herradura; since then I have had the cargo discharged and the ship hove down, and I am happy to say that the damage is trifling to what I expected. The ship struck the rock between the stem and main keel, and I find she has split about three feet of her keel, which is already repaired, and I shall commence taking in my cargo on the 19th instant, and leave this for Herradura on the 30th instant. On my arrival here from Herradura, I went on board the commodore's vessel (her Majesty's ship Stag) and saw the master, to whom I pointed out the situation of the rock; he then referred to the chart, and said it was a most extraordinary thing, as it was only surveyed by her Majesty's ship Beagle the year before last. Commodore Sullivan requested me to let him have a sketch of the harbour from my chart, which I have done. I have also made some remarks for entering the harbour, and they are now printing new charts, taking mine for a copy. It is singular that there have been upwards of eighty vessels loading in that port, and no one knew that the rock was there. It is nearly in the centre of the harbour, with from two and a half to three fathoms water over it."

[We insert the foregoing from a recent copy of the Times, as a caution to vessels frequenting the ports of Herradura, of which there are three separate ones on the coasts of South America, in the Pacific Ocean; namely, Herradura de Carrisal, in about 28°,

Herradura de Quintero, in about 321°, and Herradura de Coquimbo, in 30° south latitude. As the notice does not specify which of these harbours the rock is in, and as it appears to be of a most important description, lying in the very middle of the port, and capable of bringing up a ship, perhaps the gentleman to whom Captain Lamotte has addressed his letter, will supply us with any further information in their power, which will enable us to bring it to light, as such an important danger cannot be too soon known. With regard to the Beagle's survey, every seaman knows the difficulty of discovering these hidden dangers, and how easily they are passed by a boat in sounding.-ED. N. M.]

SUNKEN ROCKS OFF CANDIA.-Eastern End.

WE insert the following from the Shipping Gazette, as a caution to masters of vessels. At the same time we may observe that there is no chart of the island on which they can be laid down, as there is some mistake in the bearings. The rocks, however, appear to lie in the channel between the island and the Yannissei islands.

ROCKS NEAR CAPE SIDERO.-Extract from the log-book of the barque Union, Captain John Temperley :-" Remarks on board, Monday, April 30, 1838, commence with light wind and clear weather, all sail set possible. At two P.M., in sailing between the Yannis Isles and Cape Sidero, observed breakers ahead, and in sailing close to them found it to be a reef of rocks, some of which were above water, a passage of about a mile between them and the main. They bear from the northernmost of Yannis Islands, N.W. W. by compass, and from Cape Sidero N.E. by N. by compass, and extended off about 2 miles and of a mile N.E. and S.E.; the water very much discoloured for about a cable's length in a N.E. direction. My cause for making a remark of them is that they are not laid down in any of my charts, nor any notice taken of such dangers in any of the books. I am of opinion that the said rocks or shoals must be the work of some volcanic eruption."

ON THE CHANGES IN THE FORM and Extent of SABLE ISLAND,

SINCE THE YEAR 1811.

Sable Island, 1837.

On the 30th of September, 1811, there was a severe gale of wind from S.S.E., that washed away all of the dry part of N.W. bar, extending four miles and a half N.W. from the high part of the island, and half a mile broad. The greater part of it was covered with grass, and on the outer part of it was a hill elevated about twenty-five or thirty feet above the level of the sea, on which the rigging and sails of a brig that was wrecked there that summer were placed for safety; but these were all lost when it washed away. There is now, over the same extent of bar, four or five fathoms of water. The sea has been

reducing the western end both since and before that time, at the rate of nearly one-sixth of a mile annual.

Easterly, southerly, and S.S.W. winds, set a rapid current along shore in shoal-water, to the W.N.W. and N.W.; that is, along the shore of the western end of the island, but not the eastern or middle, as there the current, with southerly and S.W. winds, sets to the eastward. The natural tendency of the flood-tide is toward the coast. When it strikes the island, it flows to the eastward, over the north-east bank, and to the westward over the north-west bank, and passes the west end in a north-west direction, so rapidly that it carries the sand with it; and the hills of the west end being high and narrow, they are undermined at their base by it, and tumble down some thousands of tons of sand at a time. This, the current beneath catches, and sweeps away to the N.W., increasing the bank. As soon as this current passes the extreme point of the dry bar, it tends more across the bank to the N.E.; the motion of the sea contributing to keep the sand in motion; the current carries it to the N.E., and spreads to the N.W. Although across the bank from the island, to the distance of fifteen or twenty miles to the N.W., there is a flood and ebb tide, the flood setting to the N.N.E., the ebb to the S.S.W., the flood comes over a broad flat bottom until it arrives at the highest ridge of the bar, bringing the sand with it so far. It then finds a deep water suddenly to the eastward of the bar, and its strength is as suddenly lost, the waters pitching over this bank settle gently in deep water, and the sand going with the current does the same, and keeps the eastern edge of the bar and the bank very steep; but to the southward and westward it is flat and shallow.

The ebb tide, setting gently to the southward and westward, meets the steep side of the bank; and rising above it, passes over and increases in strength, merely levelling the sand that had been brought up by the last flood. It does not carry it back until the next flood comes, which brings up a fresh supply from the washing of the island; and so alternately the sand changes with every flood and ebb tide. The consequence is, that although the west end is several miles to the eastward of where it was in 1811; yet the shoalest or eastern part of the bar or bank has the same bearing from the dry land that it had then, which plainly shows that the bar and bank have increased eastward as fast as the island has decreased in the same direction. But the distance of the outer breakers has not increased more than about two miles; in 1829 their whole distance from the land being from ten to fourteen miles, in rough weather bearing N.W. from the island. There is a passage across the bar inside, about four or five miles broad, with three or four fathoms of water. Since 1811, or about twenty-six years, an extent of four miles and a half of high land has been washed away, which averages rather better than one-sixth of a mile every year. In the last few years it is nearer to one-fourth of a mile every year, owing

to the land being much narrower than it was the first fifteen years of the elapsed time. The whole of the island that does not wash away, grows in height; the most windy seasons cause the greatest elevation of parts where loose sands can be blown on to them; but the island in general grows narrower.

The eastern end of the island has not wasted much in length since my knowledge of it,-nearly thirty years. The high land (about a mile. of it) has blown down with the wind, (but not washed down with the sea, as at the west end,) and now there is a low, bare, sandy beach, extending in a N.E. direction from the high land about three miles. I think about one mile of this was high land, or sand hills, thirty years ago; the other two miles were formed by a low sandy beach, as at present: the elevated portion of the one mile of course has been blown into the sea, and gone to increase the shoal-water on the bar, being carried there by a strong flood-tide setting to the N.N.E. The bar itself extends from the dry part E.N.E., and at the distance of twelve or fourteen miles from the high land, a very shoal spot, always breaks, except when dry, at which time seals may be observed lying on it. Between this spot and the land is a passage about five or six miles wide, with from three to four fathoms of water on it. This bar and bank is also very steep on the north western edge, and shallow and flat on the opposite directions. The bar travels to the northward slowly, the N.W. bar travels to the northward and eastward rapidly. The variation of the compass, by amplitudes, on the 9th February, 1837, was 20° 22' west, and I think increasing.

The lake in the island fills up very fast, generally by sand blowing into it from all directions, and partially by the sea flowing over the south coast in many places in heavy weather, and conveying the sand with it. The improvements on the island have very much increased within the last few years. When the French frigate was cast away in 1822, the crew, all except the officers, had to cook and live in the little hollows and sheltered spots about the island, for the want of buildings to cover them; and yet they were grateful and uncomplaining. I have since seen Englishmen, with a comfortable house over their heads, good convenience for cooking, and plenty to eat, yet dissatisfied and grumbling. There are now seventeen considerable buildings on the island, besides some three or four small ones, that would upon an occasion afford shelter to four or five hundred persons. JOSEPH DARBY. To the Honourable Collector of Her Majesty's Customs

at Halifax, N.S

(Signed)

ON CHASING.-By Lieut. Henry Raper, R.N., V.P., R.A.S. [Read at the Evening Meeting of the U. S. Museum, May 7th.]

THE principles of chasing have been laid down by writers on tactics, but though few and very simple, the knowledge of the principles