HYDROGRAPHY. Note.-All Bearings are Magnetic, unless otherwise stated. 1. THE VIRGIN ROCKS, Bank of Newfoundland. LATITUDE 46° 26′ 15′′ N. LONGITUDE 50° 56′ 35′′ W. Soundings 4 fathoms. THAT the situation of these rocks should have remained uncertain, and even that their existence should have been doubted, to a very recent period, affords an instance of one among the many difficulties with which hydrographers have to contend in the construction of charts. Although repeatedly sought for, they were known. only to a few fishermen, who frequent the Banks of Newfoundland, until the enlightened views of Vice-Admiral Sir Charles Ogle, Bart., for the safety of our North American traders, led to their complete discovery. To the laudable exertions of this officer, while commander-in-chief on the North American station, navigators are indebted for ascertaining their correct position, besides various other important and valuable observations on that coast. In the month of July, 1829, the Inspector, tender, under the charge of Mr. Edward Rose, Master in the Navy, accompanied by His Majesty's Sloop Manly, Lieut. (now Com.) Bishop, were sent by Sir Charles Ogle, to look for and determine the position of these rocks. His Majesty's Sloop Inspector was anchored about one hundred fathoms to the north-east of the shoalest part of the rocks, in the above position. The observations were made with a circle by Worthington and Allen, and two chronometers, the latter with a rate six days old from Halifax. Their meridian distance from Halifax was found to be 12° 42′ 6′′ E. and the longitude of the rocks depends on Halifax dock-yard, which is supposed to be in 63° 38′ 41′′ W. of Greenwich. The Inspector lay at anchor forty-eight hours, during which time the above result was obtained from a series of observations with a well-defined horizon and favourable weather. Mr. Rose describes the rocks as extending in an irregular chain, or cluster, 800 yards in the direction of N. E. by E. and S. W. by W., their breadth varying from 200 to 300 yards. They were distinctly seen under water, particularly a large white mass of rock, in 4 fathoms, having 5 and 6 fathoms round it. The shoal was traced in 7 fathoms, on detached rocks, near the edge of it, having deeper water between them. On the southern edge of the shoal, from S. E. to W., the depth increases gradually to 30 fathoms, at the distance of half a mile from the shoalest part. The same depth was found to the N. W. and N. E. of the shoal, at the distance of one-third of a mile, and also between N. E. and S. E. at the distance of one mile. The bank on which the Virgin Rocks are situated, was found, by Mr. Rose, to extend four miles and a quarter, in an E. by S. and W. by N. direction, and two miles and three-quarters in its broadest part, the depth being regular from 28 to 30 fathoms. Beyond these limits, the depth increased suddenly to 39 and 43 fathoms. The current was found setting to W.S.W. at the rate of one mile per hour over the shoal, with a confused cross-swell. The Manly, whilst at anchor on the bank, was obliged to strike her top-gallant masts; and the swell was so considerable, that the vessel rolled the muzzles of her guns under water. The Manly remained at anchor one night, and, on getting under way in the morning, the chain cable broke in the middle, owing, it was supposed, to the violent friction which it had undergone against the rocks. In an easterly gale, which would be attended with the whole swell of the Atlantic ocean, no vessel could pass over these rocks. They lie in the direct track to Cape Race, Newfoundland, the point which vessels, bound to Quebec, generally endeavour to make. The following accounts of the VIRGIN ROCKS, previous to their discovery by Sir Charles Ogle, afford some further particulars relating to them : By Captain Cummings. "Lat. 46°. 27'. N. lon. 51°. 8'. W. Soundings were had in 23 fathoms, one mile to the northward. Captain Cummings states these rocks to be of a triangular shape: breakers very heavy. The bearings from Cape Broyle S.E.S. 80 miles." By Captain Kemp. "Lat. 46° 30′ N. lon. 50° 51′ W. Cape Broyle, S.E. § S. 84 miles." By Mr. Moore, of Ferryland. "Mr. Moore has frequently been on the shoals, and had vessels fishing on them. E.S.E. from Cape Race, by compass, are the Virgin Rocks, near and around which you will have 40 fathoms. Immediately on them he has, in his long-boat, held one end of the kelp in his hand, while the other end was fast on the ground, in about 2 or 3 fathoms water. From Ferryland Head the course is S.E. by E. by compass, 75 or 80 miles: E.S.E. by compass, distant 3 or 4 leagues from them, are the Scotch rocks. This information, I trust, will enable you to ascertain their particular situation; a thing which, when the bank fishing was prosecuted extensively from hence, was as well known to the masters of the bankers as any particular part of the coast; and indeed appears to have been their general and invariable resort during the months of June and July; that is, the caplin season." By Captain Codner "The Virgin Rocks lie in lat. 46° 33′ N., and from 68 to 71 miles east of Cape Race, as nearly as possible. These rocks are three in number, and lie about three-fourths of a mile from each other. One is a white, and the other two black rocks, with their kelps up on the water's edge. The water upon them, when low, is 3 or 4 fathoms." By Mr. Michael Haley, of St. John's. "From Ferryland always steered S.E. by E., by compass 81 miles; anchored in 27, 15, or 12 fathoms. Saw them break heavily once when I was a little to the eastward of them: observed the shoal to break about the length of 5 or 6 miles. The shoals seem to extend about N.E. and S.W.; blowing hard at the time from the N.W.; was in a vessel about 50 tons, a banker. The Trepassey fishermen, who constantly fished on them, always took their departure from Cape Race, and steered about E.S.E. by compass: knew when they were among the rocks, both from the shoalness of the water, and from the chain-cables coming up much brightened. Sixteen years ago I was there, and fished on them constantly for seven or eight years. Have heard numbers say, that they have frequently anchored in five fathoms water among the rocks. The shoal appeared, from the breaking of the sea, not to be of much breadth." 2. THE PRINCESS ELIZABETH SHOAL. LAT. 38° 16' N. Lon. 39° 49′ W. Extract of a letter from Lieutenant Scott. West of the Azores. "On the 24th of April, 1828, at three o'clock P.M., I came on deck, and immediately observed the water round the ship very green, and with every appearance of being in soundings; and, on looking before the starboard-beam, saw under water, at the distance of about two cables, what evidently appeared, to the master and myself, to be a white sand-bank or rock, which the water did not then break on, but it appeared so very plain, that there could not be much water on it. In extent it was about one, or one and a half cable E. by N. and W. by S. (true bearings), and about half a cable in breadth. Immediately on observing the shoal, I ordered the lead and line up, but, ere it was ready, the colour of the water had changed to a deep sea-blue, when it was evidently no use to sound: at that time we were about a mile from the white spot; we had at the time a good breeze, but very little swell of the sea, for the Atlantic ocean. I obtained two sets of lunar distances the day before; and at noon on the 23rd had taken myself, with a sextant, the meridian altitude very particularly, in order to obtain the time correctly, for lunar distances, on the opposite side to those taken on the 23rd; and which I did obtain, and made the latitude of the shoal 38° 16' N., and by the mean of the lunars, which differed very little, in longitude, 39° 48′ 49′′ W. Owing to a defect in my chronometer, I was not enabled to bring forward the longitude by it, but every care and attention in my power has been taken to give its correct "EDMD. SCOTT, situation. "Commanding the Princess Elizabeth Packet." 3. THE DRUID ROCK. N. W. of the Azores. LAT. 41° 19' N. LON. 41° 35′ W. Supposed above water. Extract of a communication made by Mr. Treadwell, commander of the Druid, just arrived in the river from Montserrat. "On the 12th of April, 1831, at 6 P.M. I passed a shoal on my starboard side, not more than 30 yards distant. Its situation on my chart (Norie's) is lat. 41° 24' N. and lon. 41° 20′ W. It being just after a calm, and having had a good meridian altitude, I consider its real latitude 41° 19' N., and longitude, by my chronometer, which has always proved correct, 41° 35' W. The shoal had the appearance of about seven or ten sugar-loaf heads, their whole length, from E.N.E. to W.S.W., from ten to fourteen feet. The westend about seven feet, and the east-end about three feet high. The Druid was lying to the wind when she passed about 30 feet to leeward of it, having previously had a calm of two days' continuance, with a smooth sea.' 4. HARPY'S SHOAL. Near Porto Bello. Soundings. 6 fathoms. Notice of a shoal near Porto Bello. "Point Manzanillo, S.W. by compass; Tambor Island, W. S. 4 miles; off shore, 3 or 4 miles. His Majesty's Ship Harpy, February, 1829, sounded in 6 fathoms, rocky bottom, and then hauling to the N.W. gradually deepened to 20 fathoms. "F. BEAUFORT, Hydrographer. 66 Admiralty, 18th July, 1829." 5. PORT ROYAL, JAMAICA.-Mark for avoiding the MIDDLE GROUND. A beacon, with a small triangle, about 50 feet above the level of the sea, has been erected on the palisadoes, between Great and Little Plum Points. When bearing N. by W. by compass, or in one with Kingston church, it will lead clear to the eastward of the East Middle Ground.-See Admiralty Plan of Port Royal. 6. RANGER ROCK.-Pictou Island, Nova Scotia. Soundings 2 fathoms. (Ship struck.) His Majesty's Ship Ranger, commanded by Captain W. Walpole, in passing between Pictou Island and Caribou Point, (coast of Nova Scotia,) on the 18th of August last, struck on a sunken rock, while in stays. The rock lies in the fair-way between Pictou Island and Caribou Point, being distant about one-third the breadth of the channel, in a W. by N. direction from the western point of the island. The circumference of the rock is about 400 yards, and the tide was found to set over it at the rate of 2 miles per hour, the flood setting to the N.N.W., making high water at full and change at 9h. 30m. On its western edge, the rock has 4 and 5 fathoms close to it, and 5 to 7 fathoms on its eastern edge. The position of this rock renders it extremely dangerous to ships leaving Pictou harbour for the westward, as it lies immediately in the fair-way. The channel to the westward of the shoal is generally adopted, in which there is from 3 to 4 fa thoms irregular soundings. 7. LATITUDE OF BENGUELA. Western Coast of Africa. M. Dourville, a French traveller, lately returned from a journey into the interior of Africa, differs from Captain W. Owen, in the latitude he assigns to Benguela. Captain Owen, in his survey of the coast of Africa, in the years 1821-6, determined the latitude on the same spot as M. Dourville, and from its being one of his chronometric stations, the observations are entitled to additional confidence. M. Dourville observed with an octant, by Gambey of Paris, and a glass artificial horizon, adjusted by spirit levels, and his latitude is the result of two meridian observations of the sun. Captain Owen's observations were generally made with a sextant and artificial horizon of mercury. The place of observation was the sea-beach, close to the custom-house, and the results were as follow: 12° 31′ 42′′ S. M. Dourville, in December, 1827 . . . . Captain Owen, in November, 1825 ... And Mr. De Mayne, in 1811 . . . . . Mr. De Mayne observed with the natural horizon from the anchorage, from whence his latitude, as given above, has been inferred. Much as we might be inclined to entertain a favourable opinion of Mr. Dourville's observations, the experience of Captain Owen entitles his to implicit confidence. However, as his correctness has been thus questioned by a foreigner, who has travelled several thousand miles in the interior of Africa, a corroboration from a future visiter is desirable. 8. LIGHT VESSEL ON THE HAISEOROUGH SAND. East Coast of England. "Notice to Mariners. Haisborough Sand. "Trinity-House, London, 2nd November, 1831. "THE Corporation of Trinity-House having resolved to establish a Floating Light near the north end of Haisborough Sand, off the coast of Norfolk, in compliance with the request of the merchants, owners and masters of vessels, and other persons, using or interested in the navigation of the east coast of England: Notice is hereby given, That a vessel is now preparing for that purpose; and that immediately after her necessary equipment, which will be completed in about two months,-the vessel will be moored at the station; and lights from two lanterns, raised on separate masts, will be exhibited on board the same, and thenceforth continued every night from sun-set to sun-rise. "Farther notice will be given when the vessel has taken the station. By order, "J. HERBERT, Secretary." "Trinity House, London, 22nd December, 1831. "The equipment of the Floating Light Vessel, intended to be stationed near the north end of Haisborough Sand being now complete, Notice is hereby given, That in pursuance of the intention expressed in the advertisement from this House, bearing date the |