ON THE CURRENTS AND TIDES OF THE MONA PASSAGE.*-By Sir Robert H. Schomburgk, H. M. Consul at San Domingo.

THE wreck of the British brig Brazilian on the 8th of May this year, ou the eastern coast of the Island of Santo Domingo near Punta Eugano,† occurred in consequence of the strong N.W.b. W. current, that sweeps the Caribbean Sea, which, combining with the trade-drift, amounts probably when not overpowered by a local current, to no less than twentyfour miles per day, and frequently surpasses it.

The Brazilian, Capt. Power, sailed on the 1st of May, 1850, from Porto Cabello, bound for New York, laden with coffee, indigo, and hides, and made on the 7th of that month at 10 o'clock A.M., the Island of Mona, bearing N.N.E.; the wind being light from E.b.N., with sultry weather, the vessel carrying all sail by the wind. At 6 o'clock P.M., Mona Island bore E.N., distant about ten miles. The master went about sunset on the fore-top-mast-head, and enquiring from the man at the helm, how the ship's head then was? received as answer, that she held her course north. Cape Engano bore then north-west, distant about thirty miles; and thinking that with a course of N.b. W., he should pass about twelve miles to the east of Cape Engano, he ordered the vessel to

*This passage has received its name from the small island lying about half way between the south-west end of Porto Rico, and the south-east end of Santo Domingo.

† Cape Engano is called by the pilots of Santo Domingo, Punta Espada, and the point called Punta Espada in the charts, is called Cabo Rafael by the pilots. 4 F

NO. 11.-VOL. XIX.

be kept as close to the wind as possible. She struck about a to 5 o'clock A.M. of May 8th, on a reef near Punta Cana, about quarter of a mile from the shore; Cape Engano bearing then N.N.E., about four miles and a half distant. The current had set, therefore, the vessel gradually from N.b.E. to N.W.

Having been informed of the wreck of the vessel, I proceeded in the Dominican man-of-war schooner Constitution, to the scene of the disaster. The passage from the harbour of Santo Domingo to Cabo Engano, is usually made in two days. We had however light winds, and experienced on approaching the Island of Saona a severe current, setting us N.W.bw. at a rate of two miles in an hour, and on rounding the east end of Saona, and approaching Punta Espada, the current set powerfully to the S.S.W. at the rate of two miles and a half to three miles in an hour, so that we found ourselves in the morning from twenty to thirty miles further from the point of our destination, than we were the preceding evening. I could only ascribe this to the influence of the tides, which are felt to a distance of six miles from the east coast of Santo Domingo, and being much stronger than the stream current, they give an impetus to the south-westward, until the tidal wave, having gradually lost the impetus with which it swept through the western side of the Mona Passage, merges again into the current.

In the case of the Brazilian, the vessel experienced in the first instance the N.W.b. W. current, which gradually and silently set her towards the shore; with the change of the tide her course was retarded, and in lieu of being at midnight, as Mr. Power expected, twelve miles to the eastward of Cabo Engano, he was at that time ten or twelve miles to the south of it, and a reef-girted shore perhaps not more than seven or eight miles under his lee. Cape Engano bore then probably N.b.E. distant twelve miles, the vessel had therefore been set three points to leeward, and had been retarded twenty miles in its course. Had the Brazilian tacked at that time she would have escaped all danger.

The Constitution on board of which I was, anchored on the 18th of May in the afternoon, near Punta Cana, somewhat more than a mile off shore. The wreck of the Brazilian was from here north one mile. We found for the subsequent three days, that the tide run with a velocity of three knots and a half for nearly nine hours, towards the S.S.W.; and merely for two hours and a half to three hours to the N.E.b.N. The pilot on board the schooner told me that he was well acquainted with this coast, and that the tides were not always of equal strength, running sometimes six hours to the S.S.W., and six hours to the N.E.; at other periods the ebb-tide was stronger than the flood-tide, and if such a case occurred, the north-easterly tide run even with greater velocity, than the south-westerly.

The great strength of the current, is to be ascribed to the swelling of the Orinoco, which river commences to rise in April, and reaches its maximum height in August. It pours then out its vast masses of waters, through its numerous mouths, sweeping along the southern shores of

the Carribbee Islands, and directing its centre towards the promontory of Santo Domingo called Point Mongon, (to the south of which lie the small islands of Beata and Alta Vela,) it forms there such an opposing mass of waters to vessels, that they are known to have been detained there for weeks.* During the inundations of the Orinoco, the velocity of the N.W.b.W. current, is along the south side of Porto Rico from one knot and a half to two knots in an hour; and the stream approaching the Mona Passage, sends an offset through the same, which continues its course, assisted by the ebb-tide, until it meets the tidal wave from the broad ocean, and overpowered by its stronger antagonist, receives a south-western impulse, until it reaches that distance from the shores of Santo Domingo, where the tides are no longer felt with violence. It merges afterwards in the N.W.b. W. current, now combining drift with stream, and continues its central course along the south side of Jamaica, until the Carribbean current rushes into the Gulf of Mexico.

The mass of water which this current disturbs in its course sweeping to the north-west, produces no doubt an indraught, which causes the tidal wave that comes from the ocean, to increase its velocity while running through the Mona Passage in a S.S. W. direction.

From September to April, the Orinoco is low; it acquires its mininum state in February. During this period the north-westerly current is weak, and any strong south wind that rises in the basin of the Carribbean Sea, will produce an accumulation of waters, which getting to the north, finds opposition by the configuration of the coasts of Cuba, Santo Domingo, and Porto Rico, and are there forced in a south-easterly direction. But this is not the only cause of a south-easterly current which is occasionally found in these localities. A northerly gale on the coast of the United States, or between the parallels of 20° and 40° north, and the meridians of 40° and 60° west, presses the masses of waters onward to the south, until they meet the barrier which the greater Antilles place to their progress; the oceanic waves rush therefore through the passages of the Bahamas and Caicos Islands, the passage between Cuba and Santo Domingo, and between the latter island and Porto Rico, &c., with fearful violence, assuming an easterly direction as soon as they reach the Caribbean Sea, and hence they set frequently at that time to the south-east from Alta Vela along the coasts of Santo Domingo and Porto Rico.

*Admiral Columbus felt this current during his second, and likewise during his last voyage; and Washington Irving observes, that the currents are here so violent that vessels are often detained for months, waiting for sufficient wind to enable them to stem the current.

+ In a paper "On the heavy swell along some of the West India Islands, called the ground sea or north sea," (Journal of the Royal Geographicai Society of London, vol. v. p. 23.) I pointed to northerly gales in the Atlantic, as the cause of this phenomenon, and observed that the period when it sets in is generally October, and that it continues though with some intermission till April and May. The causes that produce the ground sea, are likewise the reasons of the south-easterly current along the south side of the great Antilles.

The coasters are well acquainted with this fact, and it often occurs that such a current shortens a passage from the city of Santo Domingo, to St. Thomas, three days. The tidal wave recedes during such periods through the Mona Passage, with the velocity which the flood tide usually possesses; but it sets from Mona Island north-eastward towards the little Island of Zacheo, near the north-western point of Porto Rico.

From all these observations it results, that a vessel bound from Costa Firma to the United States, that purposes to sail through any of the passages that the Caribbean Sea affords, should consider at what period the passage is made, and if between April and August the greatest caution ought to be used in passing any of the outlets from the Caribbean Sea to the Atlantic Ocean. It will be always on the safer side in passing by the Island of Mona, to consider that the stream, whether the consequence of currents or of tides, sets to the leeward, except actual observations prove to the contrary.

I have now for more than twenty years collected data respecting the N.W.b. W. current that sweeps the Caribbean Sea, its existence is sufficiently proved and generally acknowledged by navigators. I propose, therefore, that in lieu of the long name which I have given to it from the point towards which it sets, it receives the better appellation of the Caribbean current. Whatever may be the little deviations in its direction which the configurations of coasts give to it, its main direction is to the north-west.

THE ARCTIC EXPEDITIONS.-Return of H.M. Ship North Star. Mr. J. Saunders, Commander, and Prince Albert, Commander H. Forsyth.

The last number of the Nautical was scarcely completed, when the North Star from Baffin Bay, with intelligence from our fleet of Arctic Ships, electrified us by her sudden arrival, and opened afresh that deep vein of painful excitement with which the recollection of Sir John Franklin and his companions is inseparably connected. Uuder the command of Mr. James Saun. ders, the North Star has acquitted herself well of her important task. The report of her proceedings made to the Admiralty by this officer, like everything connected with Arctic affairs is so deeply interesting at the present moment that we preserve it entire in the Nautical.

Mr. Saunders says:

Her Majesty's Ship, North Star, Spithead, 28th September, 1850.

AFTER the boats of the Prince of Wales whaler left the ship on the 19th of July last year, I proceeded along the edge of the ice in search of an opening to get through the pack (as there was no land floe in Melville Bay,) being occasionally compelled to make fast to a berg, or large floe, whenever our progress was impeded, either by the closing up of the ice or calm weather. In this way we continued making little or scarce any