Pentland Firth

A historical perspective, drawn from the Ordnance Gazetteer of Scotland: A Survey of Scottish Topography, Statistical, Biographical and Historical, edited by Francis H. Groome and originally published in parts by Thomas C. Jack, Grange Publishing Works, Edinburgh between 1882 and 1885.

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Pentland Firth, a strait along the E portion of the N coast of Caithness, separating the Orkney islands from the mainland of Scotland. Its length, from a line drawn on the E from Duncansbay Head to Old Head at the SE point of South Ronaldsay, to a line drawn on the W from Dunnet Head to The Barry in Hoy, is l4 miles. The width from Duncansbay Head to Brough Ness in South Ronaldsay is6 ¼ miles, and the width from Dunnet Head to Tor Ness in Hoy is 7¾ miles. In the centre the width is greater, as a triangular projection, measuring 10 miles along the base from E to W and 4 deep, is sent off to the N between the islands of South Ronaldsay and Flotta and Walls, and passes by the Sound of Hoxa into Scapa Flow. Three and a half miles WNW of Duncansbay Head is the island of Stroma, included in the county of Caithness, and separated from the mainland by the Inner Sound (1½ mile). Six and a half miles N by W of Duncansbay Head is the island of Swona, included among the Orkneys and belonging to the parish of South Ronaldsay, and 4¾ miles NE of Duncansbay Head; and at the eastern entrance to the Firth are the Pentland Skerries, consisting of Muckle Skerry, with Little Skerry ¾ mile S by E, Louther Skerry ¾ mile SE, and Clettack Skerry 1 mile E by S. The two last are tidal, and as the whole group lies right in the middle of this much frequented passage, and at a point where approach to either shore is dangerous from the strength of the current, it early became necessary to mark them by night, for which purpose a lighthouse was erected on the Muckle Skerry in 1794. The rocks are at present marked by two fixed lights placed in towers, one of which is 170 feet, and the other 140 feet, high. These are 100 feet apart from SSW to NNE, and are visible at a distance of 18 and 19 nautical miles. The only inhabitants of the Skerries are the lighthouse keepers and their families, who numbered 19 in 1861, 14 in 1871, and 17 in 1881. Though the Pentland Firth is the most dangerous passage in the British seas, it must be traversed by all vessels passing from the E of Scotland to the Atlantic, or from the W to the North Sea, except those small enough to be accommodated by the Caledonian Canal, and hence over 5000 vessels pass through every year in spite of the danger and difficulty of the navigation. This danger and difficulty arises from the extreme rapidity with which the tidal current here runs-from 6 to 12 miles an hour-and from the eddies by which it is in many cases accompanied. The chief of these latter, which are caused either by turns of the tide-race or by sunk reefs forming obstructions along the bottom, are the line of breakers off Duncansbay Head known as the ` Boars ' or ` Bores of Duncansbay; ' the line of breakers off St John's Point midway between Duncansbay Head and Dunnet Head, known as the ` Merry Men of Mey; ' the whirlpool at the N corner of Stroma, known as the ` Swelkie ' (see Orkney); and the whirlpool near Swona called the ` Wells of Swona. ' The current during flood flows from W to E, and during ebb from E to W, and ships hale to wait at either end till the set of the stream is in the direction in which they wish to pass, as it is utterly useless to attempt to push on against the flow. The stream along the coasts flows in a direction opposite to that of the central or main current. ` The flood tide, ' says the writer of the account of the parish of Dunnet in the New Statistical Account, ` runs from west to east at the rate of ten miles an hour, with new and full moon. It is then high-water at Scarfskerry [midway between Dunnet Head and St John's Point] at nine o'clock. Immediately as the water begins to fall on the shore, the current turns to the west; but the strength of the flood is so great in the middle of the firth that it continues to run east till about twelve. With a gentle breeze of westerly wind, about eight o'clock in the morning, the whole firth seems as smooth as a sheet of glass, from Dunnet Head to Hoy Head in Orkney. About nine the sea begins to rage for about 100 yards off the Head, while all without continues smooth as before. This appearance gradually advances towards the firth and along the shore towards the east, though the effects are not much felt upon the shore till it reaches Scarfskerry Head, as the land between these points forms a considerable bay. By two o'clock the whole firth seems to rage. About three in the afternoon it is low-water on the shore, when all the former phenomena are reversed-the smooth water beginning to appear next the land and advancing gradually till it reaches the middle of the firth.' These opposite currents are perplexing to those unacquainted with the Firth, but the boatmen of the adjacent coast know them well, and invariably make use of them when sailing about. In a calm, more particularly during a fog, the danger is increased rather than diminished, for ships drift along while the crew believe them to be stationary. At full spring tides the rise of the sea is 8 feet, and on extraordinary occasions 14 feet, while at neap the rise is from 3½ to 6 feet, and the firth is most stormy when a spring flood-tide is running against a gale blowing from the opposite direction. The islands and the adjoining coast suffer most severely when gale and flow act together. ` The great storm of December 1862,' says Mr C. W. Peach, ` in particular distinguished itself by the havoc which it wrought along these shores. It swept the sea over the north end of the island of Stroma, which lies in the Pentland Firth, and redistributed the ruin-heaps there. The waves ran bodily up and over the vertical cliffs on the west side, 200 feet in height, lodging portions of the wrecked boats, stones, seaweeds, etc., on the top. They rushed in torrents across the island, tearing up the ground and rocks in their course towards the old mill at Nethertown on the opposite side. This mill had often before been worked by water collected from spray thrown over these cliffs, but never had such a supply been furnished as by this gale. One curious phenomenon was noticed at the south end of Stroma: the sea there came in such a body between the island and the Caithness coast, that at intervals it rose up like a wall, as if the passage was too narrow for the mass of water which, forced onwards from the Atlantic between Holburn Head on the Caithness shore and the Old Man of Hoy on the Orkney side, passed bodily over the cliffs of Stroma.' Even in summer the effects of a gale is often grand and almost sublime. ` Nowhere else, ' says Dr Archibald Geikie, ` round the British islands can the tourist look down on such a sea. It seems to rush and roar past him like a last river, but with a flow some three times swifter than our most rapid rivers. Such a broad breast of rolling, eddying, foaming water! Even when there is no wind the tide ebbs and flows in this way, pouring now eastwards now westwards, as the tidal wale rises and falls. But if he should be lucky enough to come in for a gale of wind (and they are not unknown there in summer, as he will probably learn), let him by no means fail to take up his station on Duncansbay Head or at the Point of Mey. He will choose if he can a time when the tide is coming up against the wind. The water no longer looks like the eddying current of a mighty river. It rather resembles the surging of rocky rapids. Its surface is one last sheet of foam and green yeasty waves. Every now and then a huge billow rears itself impatiently above the rest, tossing its sheets of spray in the face of the wind which scatters them back into the boiling flood. Here and there, owing to the configuration off the bottom, this turmoil waxes so furious that a constant dance of towering breakers is kept up.. solid sheets of water rush up the face of the cliffs [of Duncansbay Head] for more than 100 feet, and pour over the top in such volume, that it is said they hale actually been intercepted on the landward side by a dam across a little valley, and hale been used to turn a mill.'

An accompanying 19th C. Ordnance Survey map is available, or use the map tab to the right of this page.

Note: This text has been made available using a process of scanning and optical character recognition. Despite manual checking, some typographical errors may remain. Please remember this description dates from the 1880s; names may have changed, administrative divisions will certainly be different and there are known to be occasional errors of fact in the original text, which we have not corrected because we wish to maintain its integrity. This information is provided subject to our standard disclaimer

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