Journal of the Royal Geographical Society of London/Volume 1/On the Vigia called the Aitkins' Rock

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Track of the HMS Onyx searching for Aitkin's Rock

IV.—On the Vigia called the Aitkins' Rock. By Captain A.T.E. Vidal, R.N. Read the 15th of December, 1830.

Of the numerous vigias dispersed over the North Atlantic Ocean, not one has perhaps excited so much apprehension, or been the subject of such frequent inquiry, as that denominated Aitkins' Rock. It is said to lie off the north-west coast of Ireland, immediately in the track of vessels trading from the westward to our northern ports; and the various positions assigned to it range from the latitude of 55° to 55° 18′ N., and from longitude 9° 38′ to 14° W.

The first notice of this supposed danger was communicated from Whitehaven on the 12th September, 1740. It states, 'that on the 15th July last, at seven o'clock at night, on our passage from Virginia, in the Friendship of Ayr, John Aitkins, master, James Lockhart, mate, saw, by the weather-leech of our foresail, a rock about four feet under water, distant, to the best of our judgment, forty or fifty yards. Our ship was running E. by S., under a reefed foresail, at the rate of six knots per hour. The wind was N.N.W., with a heavy swell from the N.W. All hands were on deck, and saw it plainly. Next morning, we made the land between Inishterhol and Tory Island, at about eight o'clock; and at noon the Mouth of Derry Loch bore S.W. by S. ten leagues, Isla at the same time being E. by S. six leagues. From these bearings, I find the rock lies in latitude 55° 18′ N., and longitude, from the meridian of London, 11° 14′ W. At the time we saw the said rock it was an hour's ebb.'

Secondly.—In Weir's History of Greenock, amongst the occurrences of the year, we read—'September 4th, 1766.—The accounts we had formerly from Captain Aitkins are confirmed by Captain Dunlop of the Bogle, who arrived this day from Virginia, and gives the following account:—

'On the 29th ult., about four P.M., we fell in with a small rock, bearing north one quarter of a mile distant. We were then sixty leagues west of Tilling Head, on the north-west coast of Ireland. Its top was rugged, and about the length of the ship's keel, and appeared seven or eight feet above water. By an observation that day at noon we made its latitude exactly 55°. The wind was blowing a brisk gale at W.N.W., and the vessel going at the rate of seven knots. When we lost sight of the rock, which was in twenty minutes, it bore N.W. by W. about two miles and a half.'

Thirdly.—The ship Nestor of Greenock, returning from New York in 1793, being in latitude 55° 19′ N., and longitude, per account, 9° 53′ W. of London, the officers, passengers, and ship's company who were then on deck, perceived a rock about four feet below the surface of the water, and not five fathoms from the weather-beam of the ship. It was in the form of a horseshoe, with one side longer than the other. The mate instantly threw an empty barrel overboard. The yawl was got out as soon as possible, and the mate, four of the crew, and two passengers, went in the boat, and were absent nearly two hours in search of the rock; but owing to the ship's drift, and a dark cloud which then obscured the atmosphere, they could neither find rock nor barrel. The Rev. Mr. Stewart was then a passenger in the Nestor, and saw the rock plainly, with the tangle growing on it.'

Fourthly.—In the Greenock Advertiser was given an extract from a letter of Mr. Hugh Faulknor, master of the ship Mary of London, stating that, on his passage from Seville to Bergen in Norway, he perceived close by him the appearance of a rock to leeward, and, from light winds, had some difficulty in weathering it. When past it, he hoisted out his boat, put some hands into her, with a deep-sea lead and line; and it being then calm, sounded all round it. At the distance of four fathoms from it, he had from thirty-five to forty feet, and at thirty fathoms' distance, no bottom, with a hundred and fifty fathoms. It was of a pyramidal form, nowise rugged, but perfectly smooth as far as could be seen below water, and not exceeding four or five feet round at the top, then appearing like a boat three or four feet above water. He had at the same time a good observation close by the said rock, and proved it to be in latitude 55° 15′ N., and longitude 11° 40′ W. From the landfall made (being the north of Lewis) exactly corresponding with his reckoning, he has no doubt but his longitude given is correct. Mr. Faulknor adds—'In 1772 I sailed with Captain Hugh Moody, and heard him say, that in 1770 or 71, in the brig Nancy of Greenock, he fell in with Aitkins' Rock, and went with a boat and sounded it. At the distance of a boat's length, had from thirty to forty fathoms; that it was small above, and rather below the level of the sea, as near as he could judge from the water washing over it.'

Fifthly.—An extract from the log-book of the True Briton, James Reid, master, informs us, that on Wednesday, 27th September, 1826, when steering E.S.E., a man at the mast-head called out that there were breakers close to us on the starboard bow. I immediately hauled the brig up, S.S.E., to clear them. In the run of the sea, a rock appeared a little above water, nearly flat, about ninety feet long and forty broad; saw no breakers except round the rock, but could distinctly see the sea working over it. We sailed from the rock eleven miles S.S.E. by compass, and observed in latitude 55° 17′ N. We then bore up E.S.E. thirty-six miles, and E. by S. six miles, when Tory island bore by compass S.W.1/2W., distant one mile and a half.'

Sixthly.—In the Greenock Advertiser of 30th July, 1827, we read—'In the brig Paddy Carey, D. Cunningham, master, on her passage from New Orleans to this port, on Wednesday the 25th inst., while running for the North Channel, at three p.m., Mr. Drain, my mate, called me and said he saw a long-boat bottom up. I ran on deck, and saw the sea roll over it; at the same time it struck me it was Aitkins' Rock, although it did not agree in the latitude by several miles. It appeared, at the north end, smooth, and the south end like the tail of a fish. The sea rolled over it, and in the hollow of the sea it was about two or three feet high, and about thirty or forty feet long. We had all sail set at the time, and were going seven knots: so that we had not much time to examine it. We had an observation the same day in latitude 55° 08′ N., and longitude 12° W. We ran E. by S.1/2S. fifty miles, E.S.E. fifty, and S.E. by E. ten miles, and made the land of Arranmore at five a.m. on the 26th. We found the vessel had been a-head of her reckoning about thirty miles, and applying this correction it would appear we passed it in latitude 55° 12′ N., and longitude 10° 30′ W. We could not exactly say it was a rock, but think it proper to report the circumstance, as it may be useful to warn mariners of a possible danger.'

Lastly.—Mr. Anthony Carrol, who had a small fishing vessel on the north-west coast of Ireland, and whom we have personally interrogated on this subject, declares to have seen the rock in June, 1820, and again in June, 1821,—on each occasion about sunrise, with light easterly winds and smooth sea. He stated his nearest approach, by estimation, was about three hundred yards. Its top was small—about three feet above water, rising abruptly on the north side, and sloping gradually on the south. There was no surf or break upon it, but merely a ripple of the waters round it. He did not examine it with his boat, neither did he try for soundings anywhere in its vicinity, which he attributes to the superstitious feeling of his people, and his account is altogether vague and unsatisfactory; yet this is one of the living evidences for its existence. Some few other situations are assigned to it on the chart, but we are unacquainted with their authorities.

Having thus detailed the various accounts which have been received of this vigia, we proceed to state, that in June, 1822, the Chamber of Commerce of Glasgow, addressed a letter to the Admiralty, informing their Lordships, that during the year 1821 no less than six vessels were missing from that port; that of late years several ships had disappeared, and never been heard of; and that a very general opinion was entertained that these losses were occasioned by the Aitkins' Rock. In this view, the Chamber of Commerce requested the Lords of the Admiralty would order some of the cruisers on the Irish station to be sent to seek out and carefully determine the position of this danger, and also to sound and trace to its western limits the great bank which extends from the Hebrides and the north of Ireland. In October, 1826, the Chamber transmitted to the Admiralty the extract from the log-book of the True Briton, and took the opportunity to renew the former application; and in August, 1827, it again applied, enclosing the report of the master of the Paddy Carey, as fresh grounds for its apprehensions.

In consequence of these representations, instructions were sent to the commander-in-chief on the Irish station; and, in 1824, his Majesty's sloop Gannet was ordered on this service; in 1827, the Harrier and Badger; and in 1829, the Pylades and Despatch—all with equal ill success: the rock was not discovered.

The Admiralty having resolved to pursue the inquiry in the summer of this year (1830), the Onyx and Leveret, two ten-gun brigs, commanded by Lieutenants Dawson and Worth, were selected for the duty, and ordered to rendezvous in Loch Swilley, the best and nearest port to the supposed danger. Particular instructions were drawn up by Captain Beaufort, the Admiralty hydrographer, for their method of proceeding in this examination; and the charge of carrying them into execution was committed to Captain Vidal, who was embarked for that purpose on board the Onyx, the senior lieutenant's vessel.

On arriving late in May, the errors and rates of the chronometers were ascertained at Buncrana,—the geographical position of which had been previously determined by the Ordnance survey. Preparatory to sailing, the brigs were swung on the different points of the compass to ascertain their local attraction, and such signals added to those in general use as the particular nature of the service rendered necessary. They put to sea on the 6th of June, when the moon was at the full; and, commencing their examination at Tory Island, proceeded nearly along its parallel of latitude to the westward of all the given positions of the rock. The two vessels were always in company; and the general practice was to sail on parallel lines distant from each other from one mile to one mile and a half by day, and closing at night to half a mile, or as much less as the state of the weather rendered necessary. During the few hours of darkness experienced on the north of Ireland at that season of the year, the vessels were hove to, that no part of the suspected ground might be passed unseen, and the leads were kept going both day and night, from the depth of an hundred and fifty to two hundred fathoms. Their distances from each other were determined every hour by the angle of elevation subtended by their respective masts, at the heads of which balls had been placed to facilitate the measurement. Their mutual bearings were taken at the same time; and men were kept constantly at the mast-heads during the day, and a vigilant look-out preserved through the night.

The parallel of latitude of Tory Island, as already mentioned, was first carefully examined to the westward of all the positions of the rock, and then traversed back again. These runs were laid down on the chart, and then other lines traced, until the whole space was explored as there exhibited. And this system of crossing and recrossing over every part of the suspected ground was persevered in until the 31st of August; when having visited every position assigned to this danger, and indeed the whole space comprehended by them, without seeing any rock, or discovering any detached bank, which could indicate its having existed, the search was relinquished, and the vessels returned to England.

In addition to the system of cruising above mentioned, the hydrographer, in his instructions, had recommended that the vessels should sweep for the rock by laying out a large scope of hawsers between them, and drifting with it over the suspected ground. To effect this he suggested two methods. The one, when the two vessels should be on the same tack, the leading brig keeping a little off the wind, with her main-topsail occasionally lifting; the hawsers fast to her quarter, with a spring to them from her weather-bow; the sternmost brig lying to, with her main-topsail to the mast, the hawsers from her weather-bow, and a spring to them from her weather-quarter. The other method he proposed was that of drifting on opposite tacks, the hawsers fastened to their sterns, with springs to them from the weather-bow of each vessel.

An additional number of hawsers were accordingly provided for the purpose at Portsmouth; and, upon the principles described, a line of them, amounting to more than fourteen hundred yards, was laid out, and a large portion of the suspected ground subjected to this mode of examination. To prevent the central part of this long scope from descending to too great a depth, and to relieve the vessels and hawsers as much as possible from the strain required to keep so much heavy rope in proper tension, the hawsers near the middle of the line were buoyed s at intervals, with empty water-casks.

Every part of the suspected ground was run and sounded over in open daylight, through the different phases of the moon, at all times of tide, and under every variety of wind and weather. Great pains were taken to explore it during the spring tides, when it might be expected to be uncovered; and, in short, the utmost diligence was exerted to bring this examination to a successful termination. This search, however, like those which preceded it, has failed to produce the rock; and though it is not presumed to assert that it has no existence, yet it is hoped that a reference to the chart will justify the statement that it cannot occupy any of the situations there assigned to it.

During the month of June, many of the mast-head men and others were momentarily deceived by the blowing of whales, which at that time were numerous; and in August a small black object, a little above the surface of the sea, was productive of similar hope and disappointment. It was first seen from the Leveret, and on examination proved to be the trunk of a very large tree, with its roots projecting two or three feet out of the water. They were covered with weeds, barnacles, and other marine productions; and presenting a rounded top, abrupt on one side, and sloping on the other, corresponded very minutely with the description of the supposed rock given by Mr. Carrol.

That fish sometimes give rise to reports of this nature, and that even experienced persons in nautical affairs may be deceived by them, is very certain, as the following anecdote, on unquestionable authority, will show:—

A frigate was one day running into the Rio de la Plata, with her studding-sails set, when the look-out man at the mast-head reported breakers on the bow. The captain believing such a danger could not have escaped the notice of the Spaniards, and having also a tolerable chart of the river, suspected it must be some floating object, and ordered the ship to he steered directly for it. The officers were on the alert; glasses were frequently directed to the spot; and all concurred in representing it a rock a little above water. Anxious looks were directed to the captain, whom they now considered unnecessarily running into danger; but that officer kept carefully watching his approach, and as the studding-sail boom was just over it, the cetaceous monster (for such it was) hastily made off, and rising again to blow, finally disappeared. It was observed to have an excrescence on its back, covered with shell-fish. The sea broke gently on its weather side, and appeared becalmed to leeward; and so perfectly did it resemble a rock, that had the vessel passed at a distance without disturbing it, there can be little doubt but it would now have had a place upon the list of vigias. In the fact here related will probably be found the history of many of those fearful marks which crowd our charts; and as the greater part of the officers of a frigate were deceived into the belief that what they saw was really a rock, is it unreasonable to suppose that similar deceptions may have given rise to some of the positions of the Aitkins' Rock? It is to be observed, in the case above mentioned, that them was only a little ripple about the body, but no breakers; and this circumstance had not escaped the intelligent eye of the commander.

The vigia, which is the subject of this paper, has been introduced to notice by enumerating the various authorities on which it rests; and those who feel interested in the inquiry cannot fail to have observed how much they are at variance with each other. The first one describes it four feet under water, without any mention of breakers, though it was blowing a gale of wind at the time. The second describes it as rugged, seven or eight feet high, and the length of the vessel's keel; and though an observation was obtained only four hours previously to falling in with it, the position assigned by this authority is twelve miles south, and one hundred and fifteen miles west, of any other on record. The third was unable to find it, though he passed within five fathoms, and hove to for the purpose; consequently there could have been no breakers on it. He further describes it as of a horse-shoe form. The fourth, who actually sounded on, and all round it, calls it a very elongated cone—the whole mass perfectly smooth, as far as could be seen under water. The fifth makes it ninety feet long, forty broad, and a little above water. The sixth two or three feet high, and thirty feet long; the north end smooth, and the south end like a fish's tail; and here again no mention is made of breakers, though it was blowing strong from the N.W. And, lastly, Mr. Anthony Carrol, who was personally communicated with on the subject, states it to be a small pointed black rock, according in every particular with the old tree which has been mentioned, and which was perfectly calculated to make such an impression if left unexamined, as was his case.

This brief recapitulation of the evidences for the Aitkins' Rock places their discrepancies in a striking point of view; and whether we regard the discordant appearances, or the variety of positions which have been assigned by them, it seems impossible they can refer to one and the same object. It may be added, that, from the experience we have had of the swell on the coast of Ireland, no rock could be so situated without producing very high breakers in bad weather, which would be visible at least two or three miles. The Frenchman's Rock lies off the north coast of Ireland, only three miles from the land, which affords it considerable protection from the western swell:—moreover, it stands on a bank of soundings of great extent, and has eleven feet water over it at low water spring tides: yet this always breaks in bad weather.

It is possible that Aitkins' Rock may have been a volcanic production, which has since subsided, like the Sabrina island of the Azores; but certainly no bank exists near any of the positions assigned to it, at the depth of one hundred and fifty to two hundred fathoms, except, indeed, those which place it on the bank which surrounds Ireland, where, according to Mr. Fauiknor, it could not be, as he had no bottom with one hundred and fifty fathoms of line, at thirty fathoms distance from it.

In closing this paper it may be well to state, that although the subject of it has defied our zeal, and the primary object of our pursuit has not been attained, yet the employment of the vessels has been far from useless, since there has resulted from the inquiry a partial delineation of that great bank on which Ireland and the Hebrides are based. Its western limits have been determined between the 54th and 56th degrees of latitude, which comprehend the space by which our northern traders approach the Irish Channel, and the chain of soundings cannot fail to he highly serviceable to them in making a landfall.

Our pilot, who had served nearly half a century in that capacity on the north of Ireland, assured us that there are soundings the whole way from Tory Island to Rockall. Our time and circumstances did not allow us to ascertain this; and it is to be regretted that at a period when Great Britain has added so vastly to the stores of hydrographic knowledge, the banks which surround her own shores are many of them unknown both in quality and extent.