North Island, (which is the northernmost island of Houtmans Abrolhos,) bears north 40° west, (magnetic) from Flag Hill, and is distant ten miles and a half, in which space there may be a passage to sea, but as there appeared to be so many straggling rocks, and the western limit of the barrier is at such a distance from the islands, that if a passage does exist, it can be but narrow, and not over safe. For four miles south of North Island is a continued reef with heavy breakers, and which may probably extend to a greater distance, towards the reef off the north-west part of west Wallabi Island, and as these reefs have been traced five miles to the north-west of that island, little space is left for a passage between them. No doubt there is an opening, on account of the long swell that rolls in between them from the westward, but it would not be prudent to risk a ship while any doubt exists.

North Island is of circular form, three miles in circumference, and with the exception of a small sandy bay on its north-east side, is surrounded by reefs; the only anchorage is off this bay, about threequarters of a mile, or a mile from the beach, in a very indifferent berth.

This island is similar to the Wallabi Islands, the base of rock being covered with a sandy soil that gives growth to a stunted scrub; the centre of the island is perfectly flat, and encircled by a marginal ridge of sand hills, the highest of which is forty-two feet; it is at the southwest part of the island, and has been named Record Hill, because a bottle, containing a paper, shewing the date of our visit, was deposited there. The observations were taken on Latitude Hill, on the east side of the island, the summit of which is in latitude 28° 16′ 16′′ S., and longitude 2° 8' 57" west of Swan River.

From the north end of this island, the reef extends as far as 28° 15' 30", which is the extreme northern limit of the Abrolhos: to the westward of the island, all appears clear beyond a mile and a half, and to the eastward of the island the reef does not extend over half a mile. Soundings may be had at a greater distance from the reef off the western side of this island, than of any of those to the southward.

When the centre of North Island bore east, four miles and a half, we found thirty fathoms, coral, and with the centre of the island N. 70° E., distant seven miles, forty-two fathoms coral, to the westward of that it deepens quickly.

There does not appear to be any outlying dangers round the Abrolhos, and with the exception of Snapper Bank, there is a very uniform depth of water, from twenty to twenty-five fathoms between the different groups, and in the space between them and the main land it is rarely over thirty fathoms.

Snapper Bank, which is the only patch of shoal water that was found detached from the different groups, is N. 15° W. (mag.) from Small Hummock Island of Pelsarts Group; its south end is distant five miles and a half; it extends a mile and three-quarters to the northward, and is three-quarters of a mile wide; the least water found upon it was six fathoms. From this bank Small Hummock Island is just visible from the deck, at an elevation of fifteen feet.

The only information respecting Houtmans Abrolhos, that has ever been hitherto made known, being merely extracts from the journals of

those who had suffered shipwreck upon them, it is not to be wondered at, if such accounts have had the effect of warning all navigators from them, hence so long a time has elapsed without their exact limit having been ascertained. They lie parallel to that part of the coast of New Holland, opposite to them, (nearly N.N.W. and S.S E.,) the southern limit of the reef off South Island, is in latitude 29° 00' S., and the northern extreme of North Island reef is in 28° 15'; the western part of which is in longitude 2° 11' west of Swan River (this is the westernmost part of the Abrolhos, and the eastern limit (which is Small Hummock Island,) is 1° 42′ 30′′ west of the same meridian.

The Abrolhos may be considered as a place of refreshment, inasmuch as fish, of an excellent quality may be taken with a hook and line in any quantity, chiefly snapper and rock fish, which prove a valuable sea stock. Wallabi may be had on the islands of that name, where fuel may also be procured, and water may probably be found in many places during rains, but cannot be depended upon as a certainty, owing to the porous nature of the rock. A small quantity was found on the Wallabi İslands in May, but of an indifferent quality.

These islands might prove a welcome retreat to vessels employed in whaling on the west coast of New Holland; they generally carry sufficient water for their voyage, therefore would only require some refreshment for their crews, and this might be procured without the trouble of lowering a boat, by merely anchoring the ship near the reefs, on the east side of the islands, or between the different groups, where in a few hours a sufficient supply of fish for immediate use, and for salting may be taken.

There is no danger beyond the breakers that form the western barrier, and as the weather is generally clear enough to admit of a meridian altitude being observed, the ship's latitude may always be known, which with a common look-out, is sufficient to keep her clear, and no dangers exist that are not easily seen from the mast-head; the only drawback to anchoring under the Abrolhos, is the depth of water, but excepting when moored in confined places, the stream anchor with a long scope of bower chain, will be found quite sufficient. The Beagle very rarely let go a bower anchor.

The prevailing winds at the Abrolhos are southerly, and the weather is usually fine; there is no stream of tide to affect a ship, and the range is under three feet. The current is influenced by the wind, and consequently is generally setting to the northward, varying in direction. amongst the islands; its velocity depends upon the strength of the breeze, but is rarely over a knot an hour.

NOTES ON THE MOUTH OF THE YANG-TSE-KEANG.-By Capt. R. D. Bethune, H.M.S. Conway.

In our last number, we announced the publication of Capt. R. D. Bethune's survey of the mouth of this great river, in one of the series of charts of the coast of China, supplied by the Admiralty, for the use of her Majesty's ships, and placed in common with all the Admiralty charts,

at the service of mercantile vessels at a very low price. We expressed a hope then that we should be enabled to publish this officer's memoir of the survey he had made, so that his information might be immediately available with the above chart. Annexed is the memoir referred to, and considering as we do the mouth of this magnificent river, as the portal through which an extensive trade will hereafter flow into the very heart of China,-the information it contains may be looked on as most important.

THE limits of the embouchure of the Yang-tze-keang are not well defined, but are included within the parallels of 31° 0' and 32° 10′ north latitude. It is divided into various channels by low islands which doubtless have been formed occasionally by deposit from the river, and reclaimed by the industry of the people: both they and the banks of the river are very low, and are defended by dykes: however during the period of our visit (August and September) no traces of inundation were visible. The largest among the islands is Tsung-ming: it lies W.N.W. and E S.E.; and is about thirty miles in length, six in breadth at the eastern extremity, and nine at the western. In the parallel of Tsungming, the shoal extends fifteen miles to seaward. Twenty miles east from Tsung ming lies an island, Sha-wai-shan, (Jaunceys Island of the Amherst voyage,) 196 feet in height: latitude 31° 25' 2', longitude 122° 6' east. From the summit Tsung-ming is just visible. Saddle Island of Amherst is also visible, bearing S.E.b.S., distant forty-two miles, and the dangerous rocks bearing S.S.E. E. sixteen miles. To the northward of Tsung-ming there are several channels with deep water; some run up for eight or ten miles, and are then barred by an islet or bank; others may, perhaps, lead up, but the approaches are dangerous or shallow, so that they cannot be recommended for vessels. They have not, therefore, been examined so much in detail as that lying south of Tsung-ming, and running on the right bank of the river. This channel, the Amherst ascended when she visited Shang-hai, and it is the only one that can be recommended for vessels of any burthen. An extensive flat lies at the entrance, over which you carry from three to four fathoms with the information I now possess, I would have no scruple to take twenty-one feet over, and I think I may venture to say, future examination will shew that a four fathom channel exists: when over the flat a deep water channel not intricate, leads up eighty miles from the entrance, the highest point reached by the Conway.

We only stopped here, by having attained as was thought, the point named in the instructions, as to all appearance the deep water still continued.

Up to this point the banks had presented one uniform flat, rarely broken by trees; but here the country assumes a new character, three hills about three or four hundred feet high appearing on the left bank, about four or five miles from the river; on the summit of one of which was a tower, and apparently a large establishment of priests, (Tongchow). On the right bank the country was also becoming hilly, some approaching near the river. No large towns were visible, but many villages. The banks are intersected by numerous creeks, in almost all ENLARGED SERIES.-NO. 8.-VOL. FOR 1841.

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of which there appeared to be junks, and many people; but the greatest number of people were observed on the left bank for five or six miles, below the three hills mentioned above.

Tides, Winds, &c. These remarks depend upon observations made from the ship, which from her change of position, renders them to a certain extent uncertain, (period August and September.)

Generally off the mouth of the river, high water at full and change, about noon. Rise at springs fifteen feet,-neaps ten feet, once eighteen feet was noted, but I judged it was exaggerated. The stream of flood comes from the eastward, drawing to the southward, about the last quarter, and round to the ebb from the westward, and so round by north; the greatest velocity measured was 4.5 knots off the northern entrances, but the usual velocity at springs is about 3.5.

In the river, off Woo-sung, high water full and change, about 1h. 30m.; rise uncertain, but from fifteen to eighteen feet; stream of flood comes from south-east round by east to north; ebb from north-west round by north.

At the furthest point reached, high water about 4h. 30m.: rise fourteen feet,―ebb runs eight hours. Flood at the neaps nearly obliterated.

July.-Bar. 29-74, ther. 78, prevailing winds south-easterly, freshening about the change of the moon.

August.-Bar. 29-78, ther. 81, prevailing winds south-easterly and northerly a day or two blow at the change with a little rain.

September.-Bar. 29.90, ther. 77, winds more variable, but drawing round from south-easterly to northerly. Blows at full and change with rain,-morning much colder than average. Temperature having been taken on the main deck is not very correct; the periodical breezes at full and change appear to increase intensely. Barometer rises with northerly winds, falls with westerly and southerly winds. One hard blow with barometer at 30-10.

As far as we went, there are no means of preventing a free passage of the river. At the entrance of the Woo-sung are two forts, bearing north-west and south-east from each other, about three-quarters of a mile apart, but as they appeared to have been newly-faced with mats, I presume much confidence is not placed in them. In addition, on the left bank, is a quay three miles in length, connected with the fort, defended by a kind of wedge-shaped traverse about six feet high and long, and perhaps fifteen feet apart. We could not make out whether they were composed of earth, baskets, or earthen pots; from scme being whitened, we at one time imagined they had been erected on the same principle as the mat-forts, to look like tents. There are two batteries along this line, one of about ten guns near the western corner of the quay, another of the same number commanding the entrance, some of the guns appear to be nine or twelve-pounders.

On our return off the place from the upper part of the river, thirty to forty junks were moored abreast across the entrance; we have seen at this place perhaps 300 soldiers. Three foolish guns were fired at the ship, from a point six miles below the forts.

Above the point there are no defences, until at a large village and building establishment for junks, where a show of about fifty soldiers

was made behind a parapet. This was the highest point the Conway reached, and I judged from the Chinese charts, that it is considered the first defence on the river. As a gun-boat might be placed to enfilade this, it is hardly worth attending to. There is also a circular fort of small dimensions, apparently useless, both for offence and defence; near this, is a hill about two hundred feet high, with a building on the top, which apparently might be made defensible, describing a semi-circle from this point, with a radius of eight miles, several heights will be included, forming I conclude, a position of some value. It is unfortunate, that to the extent of half a mile from the shore the bank is very flat. Ten miles below this, on the same side, about twenty soldiers appeared in a round fort, with the usual allowance of flags.

Tents appeared in various places, when we remained any time, and a flotilla of boats followed our movements inshore, till the last moment, when a couple of shot and a shell showed them such attention, in future, might be attended with danger.

Supplies. Cattle and small stock appeared plentiful, particularly on the north side of Tsung-ming. Caution must be observed in foraging, for the country presents singular advantages of defence, the communication being by narrow causeways through the cultivated ground, which again is intersected in all directions by creeks and ditches; this, however, may only be the case near the river.

The water of Woo-sung is perfectly good; we have used it twenty miles lower, but the time of the tide must be attended to, and even then it has a trace of salt.

All the islands without the river at this time (September) can afford supplies of sweet potatoes.

I should add, that cattle appear to be kept for agricultural purposes, and it is a question whether they be easily replaced.

I annex a short report from the surgeon, Mr. Francis Sharpe, on the climate, but in justice to him, must state, that the short notice given, would not admit of a more detaile 1 statement being prepared.

Climate. During a period of ten weeks (July, August, and September,) seventy cases of dysentery have occurred, and from the alluvial nature of the land, they assumed a severe form. Several cases of fever made their appearance, two of which were remittent, and of a violent type. The climate was anything but favorable to some long standing cases of intermittent fever, two cases of cholera, one of the true Asiatic form, occurred during the month of August, which I consider to be the most sultry part of the season in China.

The mortality which has taken place amounts to five, but this cannot be ascribed to the climate, as two died of mortal wounds received in a skirmish with the Chinese, one from serious apoplexy in a man of very dilapidated constitution, and the remaining two from chronic and acute dysentery; but here it must be mentioned that these latter were constitutions totally undermined, one by two years sickness from that disease, and the other by repeated attacks of ague.

Upon an average, the weather has been fine, latterly the days have