cannot be very incorrect, as it was placed by chronometer a few days only after leaving Sydney. In approaching the positions assigned to this and similar shoals, great caution should be used, and their vicinity avoided as much as possible, for the sea thereabouts is strewed with many shoals, some of which may be yet unknown. It seems strange to me that merchant ships are not better supplied with Admiralty charts. It is well known that Norie's, and other compilations, are corrected from time to time from Admiralty charts; why not, then, use the originals, particularly when they can be purchased for a very small sum compared with the price of Norie's General Chart. Yours, faithfully, PHILIP P. KING, SAILING DIRECTIONS FOR ENTERING THE PORTS OF TAHITI AND MOREA. In the Island of Tahiti there are cleven good harbours, namely, Taunoa, (properly Taaone,) Papeeti, Rautirare, Temarauri, Tapueraha, Vaiau, Vaiurua. Vaionify, Tefaaoo, Pueu, and Vaitoare; in addition to these harbours, which are the principal ones, there are the following smaller and inferior ones, namely, Taapuna, Maraa, Teahifa, Hotumatuu, Teputa, Havae, Temotoi, Hitiaa, Mahaena, and Papaoa. Taaone on the N.W. side (known as Taunoa,) has both a good entrance and anchorage. The latter is in 13 fathoms on the east side of the bay; from this harbour there is a good passage inside the reef to Papeeti, the harbour of Taaone may be known by a peculiar mountain at the head of Faataua valley, much resembling a crown, when the crown opens on the eastern side of the valley you are abreast of the passage. Papeeti Harbour is perhaps the best in Tahiti, the passage through is narrow, in consequence of a bar extending from the southern reef two thirds across the passage; in entering it is necessary to keep close on the larboard ⚫ hand. Taapuna Passage, on the West side, is about five miles to the southward of Papeeti, and is small and difficult, having shoals in the centre of it. Course in N.E.b.E., when inside the reef keep close to the east side to avoid the shoals, which can be seen from the mast-head; when in, haul to the northward into good anchorage. There is a good passage from Taapuna to Papeeti inside the reef. At Taapuna the current sets out. On the shoals the water is from 1 to 3 fathoms; between them the water is much deeper. Maraa Passage is on the S.W side of the island; course in, N.b.E. Keep close on the starboard hand after entering the outer reef. Pass if possible to the eastward of the shoals which lay in the inner part of the passage; but a vessel can pass either between or to the westward of them. Close to the east shoal on the eastern side is a small sunken patch, but this is only to be feared by vessels of a heavy draught of water. Good anchorage in shore abreast of the passage, off a water run, There is a good passage for ships inside the reef from Maraa to Papara, where they can anchor at the Piraa orie; the current sets out at Maraa to the S.E. Rautirare Passage at Papeuriri is good, with a fine harbour. In standing in for Papeuriri there are two small islands to be seen inside the reef. These two islands are a good guide for the passages of Rautirare and Teahifa. The eastern island is situated close to the east side of Rautirare Passage; the other is about a mile to the westward; and the passage of Teahifa in Maripehe to the westward of that. In entering Rautirare keep on the eastern side, particularly if the wind should be light, as the current sets down on the lee or western reef: the course in is N.N.W. After entering the reef keep on the starboard hand. There is good anchorage under the island, although anchorage can be had in any part of the bay; the best is in the next bay to the westward near the island. Keep close to the point in passing, for although the passage is good it is narrow. In leaving this anchorage, you have the advantage of the passage of Teahifa, it is narrow, but safe at most times. Keep close to the east side of the reef to avoid a bar which runs from the west side half passage. The course, in Teahifa Passage, is N.N.W.; anchorage in shore of the island, or to the westward half a mile off Mairipehe. Temarauri at Papeari, on the south side of the island, near the isthmus, is a good passage. Course in, N.W.W. There is a small shoal in the centre of the bay; but it can easily be seen from aloft; you must pass to the westward of it, then steer for the point of Motuoini, which must be passed close. There is good anchorage round the point to the westward; small vessels can run to the westward and go out of Rautirar at Papeeuriri; the current sets out of Temarauri to the southward. Hotumatuu, on the south side of the isthmus, is direct in for Taravao, but it can only be attempted by small vessels having a fair wind; there are two or three shoals in the passage, but they are seen from aloft. Teputa Passage is close to Hotumatuu, facing the Taiarapu side. It is narrow, but has plenty of water and free from shoals; as it can only be entered with a fair wind, it can be seldom used, but it is a good passage to go out by as the wind in general is from off the isthmus; the current sets out to the southward. Tapuaeraha, on the west side of Taiarapu, has a fine and large entrance. Course in, N.E.b.N. In entering, keep well on the south side, as from the north side the shoal or spit runs off some distance; in general, here, there is a heavy rolling sea; after you are inside, you can anchor in any part of the harbour. There is a good passage inside the reef from this harbour to Taravao, which is generally taken by ships, more especially heavy ones. It is, however, rather difficult for large ships to enter this harbour of Tapuaeraha, as the wind mostly blows out, and it is not pradent to tack through fear of missing stays, the wind being so baffling off the mountains. The best way of entering is to round the reef as close as possible, then luff up, clew all up, and let go the anchor; then warp in till you have sufficient room to make sail to work up the harbour. The current sets from this passage to the southward. Havae, at Teahupoo, on the south side of Taiarapu, has a good entrance, course in, N.b. E.E.; the anchorage in the bay is only good in fine weather. For small vessels there is a narrow passage to the westward, close in shore into the next bay, where the anchorage is safe. There is a passage for small vessels inside the reef from Teahupoo to Mataoae. Vaiau, on the S.S.E. part of Taiarapu, has a fine harbour; course in, north. After entering the reef, haul up to the N.E., towards a low point into good anchorage; the current in this passage sets to the S. E. Off the Pari, on the S. E. part of Taiarapu, is a dangerous rough place full of sunken shoals, extending two or three miles off the land, and about four miles along the coast, finishing at the Motoî, which is to be known by two small islands. There is an inferior passage at the Motoî; course in W.N.W. In going in or out, haul close round the north reef to avoid the sunken shoals; having the two islands on the starboard hand in entering, haul round the islands to the northward into anchorage. NO. 8.-VOL. XXI. 3 T Vaiurua, on the eastern part of Taiarapu, has a good harbour; course in, S.W. This harbour is about two miles north of the islands at the Motoî. Vaionifa, on the N.E. part of Taiarapu, has a fine entrance; course in S.W. b.S.; the anchorage is extensive. After entering in hauling to the southward, there is a shoal; vessels can pass on either side of it. There is a passage inside the reef from this harbour to Vaiurua. Vessels can enter and depart by either as the winds may allow. There is also a good passage from this harbour close down to Tautira point. Tautira Bay is exposed to the westerly winds, and only to be recommended in fine weather. The best anchorage is close on the N.E. side under the point; on the S.W. side of the bay is a good harbour, called Fefaaô. Vessels entering the bay of Tautira should steer to the S.W, and then enter the reef to good anchorage; from Tefaaô vessels can go inside the reef to Pueu. Pueu has a good passage; course in S.S.E. in entering, haul round to the west side of the reef, and steer to the westward round the first point, and come to anchor off the village. In leaving Pueu, vessels can go out of a passage to the westward. Vaitoare Harbour, about two miles north of the isthmus, has a fine and safe anchorage. Vessels can enter or depart from the northward or southward; but the northern passage is the best. Tematoe. About two miles to the southward of the point of Ilitiaa, there is a good entrance into the reef, called by this name of Tematoe; vessels can pass inside close to the point of Hitiaa, into good anchorage. Hitiaa is on the N.E. part of Tahiti; but the harbour is not good, the bottom being rocky. After entering the reef, haul to the northward, and anchor near a small island. In leaving Hitiaa, vessels can go out by Mahaena, the best anchorage at Mahaena is in shore of a small low island, known as Nansouty's Island. To be Continued. AITKIN'S ROCK.-A report has appeared in the Greenock Advertiser and thence copied into the Shipping Gazette, that this rock was seen on the 21st ult. in lat. 55° 15′ W. and lon. 9° 56′ W. by the "officers and crew" of the barque Fingalton, Craig, of Glasgow, from Quebec to the Clyde. It is now above twenty years since this reputed danger has been expunged from our charts, after a careful search by Captain Vidal, R N., the account of which will be found in one of our former numbers, and which was published more at length along with a chart of his track, in the first volume of the Geographical Society's Transactions. Its revival on such authority, without soundings being had, is very improbable. Her Majesty's Government has been officially informed of the following lights having been established on the north coast of Spain : CAPE MACHICACO. On the 21st instant a revolving light, displaying flashes every four minutes, in latitude 43° 28′ 0′′ N. and longitude 2° 49' 10" W of Greenwich, was lighted, at an elevation of 264 feet above the level of the sea, and in clear weather can be seen 18 miles. POINT GALEA. A fixed light has been placed, on the 21st instant, on the Point of the Fort Galea, being the eastern entrance of the Port of Bilboa, in 43° 22′ 36′′ N. and 3° 3′ 46′′ W. of Greenwich, at an elevation of 386 feet above the level of the sea, and in clear weather is visible 22 miles. CAPE PENAS. A revolving light was established on the 15th instant on Cape Penas, in 43° 22′ 20′′ N. and 5° 47′ 42′′ W. of Greenwich, displaying flashes every 30 seconds, at an elevation of 343 feet above the level of the sea, and in clear weather may be seen twenty miles. THE ISTHMUS OF DARIEN. Terra Firma Proper, on the great Western Continent, was one of the earliest discoveries of the great Columbus, and is now known to form a large part of that isthmus which connects, by a continued link of land, North and South America. It extends in a N.W. direction from the lat. of 8° N. in the meridian of 76° W. long, to the lat of 16° 30′, and 1×° 30′ N. in the meridian of 95° W. long. a distance of upwards of 1,300 geographical miles. The narrowest parts are, first, between Chagres and the Bay of Panama-33 miles in a direct line; second, through the province of Chiriqui in Veragua, 40 miles, in the meridian of 82° W. long.; thirdly, from near Alvarado, in the Atlantic, to the Bay of Tehuantepec, in the Pacific-a distance of 92 geographical miles; and, fourthly, from the mouth of the river St. Juan, on the Atlantic, in lat 10° 40′ N., to Nicoya, on the Pacific-in a direct line 120 geographical miles, but from Matena only 95 miles; and, fifthly, from the Gulf of Dolce, at the bottom of the Bay of Honduras to Trinidad, in the Pacific, 70 geographical miles. Ever since the discovery of this isthmus, and it became known that it was bounded on its southern shores by the Great Pacific Ocean, the attention of Europe has been directed towards it; but while the whole of the west coast of America to the 42° of N. latitude remained under the dominion of Spain, and was sealed by her from the commerce of foreign nations, little opportunity was had of ascertaining the capabilities of this isthmus, and the means afforded by it of communicating with the Pacific Ocean from the shores of the Atlantic. But since the authority of Spain was overthrown in that quarter of the world, and the power and dominion of the United States has been extended to the shores of the Pacific, the increased communication with the islands in the South Sea, and the great rise and extending trade of the British colonies of Australia, Van Diemen's Land, and New Zealand, the attention of the world has been steadily and strongly directed to find the easiest and most practicable route by which this isthmus can be crossed, in order to afford a more rapid and safe communication with all the shores of the Pacific and the islands in the South Sea than by the long and dangerous navigation round Cape Horn. Every practicable point has been examined, and the desirable object can no longer remain uncertain or doubtful, and is, it may now be confidently stated, about to be attained. There are eight points where the communication from the Atlantic to the Pacific is more or less practicable, and more or less difficult. First, by a junction of the head waters of the river St. Juan, which fall into the Pacific in 4° N. lat., with the head waters of the Atrato, which, after a course of 210 miles almost due north, falls into the Atlantic in the Gulf of Darien. This junction is easiest through the valley of Rapadura, in which valley canoes can pass in water, during the rains, from river to river. But this valley is of high elevation, and both rivers very rapid, the distance from sea to sea 350 miles, and through very unhealthy spots. The Spanish government, about 70 years ago, had decided to try a communication at this place, but the breaking out of the American war and the French revolutionary war, diverted their attention from the project. Secondly, a line from the mouth of the river Tupica or Cupica, on the Pacific, in lat. 7° 30′ N. to the Atrato, by the river Naipi, a deep stream, and the distance from the Atrato to the sea, only about 60 miles. The summit level, however, of the valley near to the head waters of the streams mentioned, at about twenty-five miles from the Pacific, is at least 400 feet, and the line subjected to the dangerous navigation of the Atrato. Thirdly, the line from the mouth of the Atrato to the Gulf of San Miguel, a distance of 65 geographical miles. The head waters of the streams, which here run in opposite directions to the points adverted to, approach near each other, but the lowest summit level of the land between them is at least 500 feet above the ocean. The mouth of the Atrato, besid being dangerous from moving sand banks, is very swampy and most unhealthy. Thus Scott well describes By Darien's sands and deadly dew; and the shores of the Gulf of San Miguel are not much, if anything, better. Fourthly, there is the line from Port de Escosses, or New Edinburgh, a good port on the Atlantic side, to the head waters of the very crooked and rapid river Chuqumaqua, which runs into the Gulf of San Miguel, and whose sources are only about 10 miles west from New Edinburgh. The Gulf of San Miguel runs about 22 miles into the country, and is of a good depth of water, but the summit level of the dividing range to the west of New Edinburgh is at least 500 feet (some accounts say 800 feet) above the level of the sea, which, as in the previous lines, must render a ship canal very difficult, if not impracticable, by any of these routes. Fifthly, we have the line from Chagres to Panama, or rather from Navy Bay, near it, the shortest of the whole, and by which a railroad (estimated to cost £2,500,000) is now in course of construction. The summit level of this line is about 360 feet above the sea, reduced by much tunnelling about 90 feet. Chagres and Navy Bay have the most deadly climates, and Panama is by no means healthy, while large vessels can only find anchorage at three miles out from the town. Vast expense must, therefore, be necessary to construct a pier there, and a breakwater in Navy Bay to shelter vessels from the north-east winds, to which it is quite exposed, especially in the winter months. Sixthly, and passing to the Tehuantepec line, the harbours on both sides, especially on the Atlantic side, are bad, and unapproachable on the Atlantic during the winter months' northers. The line has to pass a large river to the east of the southern end of the Sierra Madre chain, which river has worn itself a bed about 500 feet deep, through earth of a volcanic mould. The elevation also is here great, and consequently a road is now only talked of, but will be difficult; a ship canal may be considered impracticable. Seventhly, we have the Juan de Nicaragua line, to which the public attention is now strongly directed, from the mouth of the San Juan, on the Atlantic, is by the river 101 miles, and in a direct line nearly 70 geographical miles to Lake Nicaragua. The river is as large as the Guadalquiver, in Spain, and all around its mouth the country is very unhealthy. Lake Nicaragua, a fine body of water, is 129 feet above the level of the Pacific, and in its deepest part 60 fathoms, shallowing to 12 and 5 fathoms in its northwest extremity. From a point to the south of the town of Nicaragua to the Pacific is about 15 miles, and the summit level of the valley, running between active volcanic mountains, is about 20 feet. There is still a narrower point to the south of the town of Granada, where the distance to the sea is only 12 miles, but by a line more difficult. Lake Nicaragua is about 120 miles long and 50 broad; and Lake Managua, or Leon, is 18 miles north-west of it. This lake is about 60 miles long and 35 broad, and ranges from 2 to 6, 12, and 40 fathoms deep. The plain of Leon is about 28 feet above it, the elevation above the sea about 200 feet, and the distance to the Pacific only about six miles, with a low ridge rising about 60 feet above the plain between them. Three lines are spoken of for a canal in this quarter. First, by deepening the river, or running a canal near the river San Juan, and then from Lake Nicaragua to San Juan de Sur, on the Pacific. But the anchorage there is not good and is subject, like the rest of rhe Gulf of Papagayo, to sudden gusts and storms of wind from the adjacent mountains; second, through the plain of Leon to the fine port of the Rialejo, lat. 12° 29′ N., and long. 87° 6′ W.; and, thirdly, by the same line to the splendid and sheltered Gulf of Fonseca, lat. 12° 40′, long. 88° 30′ W. In the latter case the distance from the mouth of San Juan will |