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luded to, is the ruin of Fast Castle, built on a magnificent cliff overhanging the waves. A little eastward from this, we reach the mouth of a naked, deep, and savage glen, equally interesting to the botanist and geologist; and, after a few additional miles, arrive at the magnificent mountain promontory of St Ebba.

“ Few parts of the kingdom can exhibit a finer and more splendid piece of coast scenery than St Abb's, to him especially who surveys it from the sea beneath, whether it be in the sum. mer season, when in calmness and security he sails over the peaceful and pellucid waters, amid gloomy caverns, rocky arch. ways, and majestic cliffs, half shattered by the storm or light. ning, and shooting up aloft their giant greatness to the skies ; or whether he visit it when the myriads of sea-fowl are clothing the lofty cliffs, or darkening with their multitudes the noon-day sun, or filling all the surrounding echoes with their dissonant voices ; or whether, when the elements of sea and sky are min. gled together, and the waves are lashed up to foam, he sits se. curely on its mountain-top, and eyes the maddening strife.

“But it is not for its mere natural scenery that St Abb's is so interesting—it is, if possible, still more so, in a geological point of view. In a sketch of this description, it may be sufficient to describe St Abb's as a huge insulated mass of trap rocks, of which the principal are, trap-tuffa, amygdaloid, and felspar porphyry. In the first of these rocks there is generally a basis of clay, with imbedded portions of basalt, amygdaloid and porphyry. In the second rock there is also a distinct basis or ground, generally of a greenish coloured clay, containing amygdaloidal shaped cavities filled with calcareous spar, zeolite, quartz nodules and agates. In the last rock the basis is generally fel, spar, with imbedded crystals of the same. When these rocks occur in the manner, and with the characters now described, it is usual to consider them as subordinate to the old red sandstone; but where no formation of this kind is observable, and where the rocks within a few yards are evidently greywacke, as they are in the situation now before us, there seems no other way of describing the trap rocks of St Abb's but as subordinate to the transition greywacke and greywacke-slate. We have described St Abb's as an insulated mountain mass, it being completely cut off from the wide extent of high ground towards the west by a deep valley, in the centre of which is a marsh of considerable botanical interest.

“ There are probably few places where the contrast, both in external aspect and in botanical phenomena, as well as in structure, is so remarkable, as it is between the two sides of this valley, especially at the little inlet termed Pettycurwick. Standing by the sea-side at this small creek, and looking westward, we perceive, for many miles along the lofty coast, the most splendid displays of stratification, the strata being of all forms, and in all positions, curved, zigzag, vertical, horizontal, &c. ; but the outline both of the summits and the slope of the precipices, we observe, in general, to be smooth and unbroken, and more like a vast sloping wall or mural defence, than a natural piece of rock-scenery. Looking towards the east again, which consists of the high ground of St Abb's, the outline is rugged, broken, and highly picturesque, the sea in that direction being ranged with beetling crags and overhanging cliffs, in one place hollowed out into magnificent caves and natural arches, and, in another, broken into wild and insulated pinTacles. In the botany of the two sides of the valley, we have

seen.

also mentioned that there is a difference, and this sufficient to attract the notice even of the most superficial observer. For instance, the Arenaria verna grows among the unstratified trap rocks of “ the head” in the most beautiful luxuriance, while, on the opposite side of the valley, though the distance in one place be not more than a few yards, not a specimen is to be

The Hypericum humifusum, again, we observe in con. siderable abundance on the stratified side, while, on the other, we do not meet with it, and the same remark I have made in similar situations elsewhere. It may be curious also to observe, that the Primula elatior, as well as the common Cow. slip, although abundant among the rocks on the greywacke side, are not met with among those of the opposite side,-a remark which holds good in other parts of the district comprehended in the following Flora.

6 Two additional remarks shall conclude our notice of St Abb’s. To the most trivial observer, it must be evident that originally St Abb’s Head has been an island of the sea, similar to the Bass in the Frith of Forth, or to the rock of Ailsa in the Frith of Clyde; it being quite clear, that the sea, at one time, has flowed through the narrow valley, but has gradually been excluded by the debris falling from each side, which has thus elevated its bottom at either end, and united at length St Abb's to the mainland,

“ The other remark relates to the probable origin of that great mass of trap rocks which forms this lofty promontory. It is impossible, we conceive, for any man who knows any thing about rocks at all, to remark the singular position of the greywacke at the little inlet already mentioned, where the two

* Rather a variety of Primula vulgaris. See P.

54.

sides of the valley approach nearest (and almost without tak. ing into account any of the other appearances equally conclusive, although not quite so evident), without coming at once to the conclusion, that some prodigious violence must have been necessary to cause the present very singular and distort. ed aspect of these strata-that this violence must have pro. ceeded from beneath-that these rocks in this manner must have been projected in a liquid form, as lavas—and that thus St Abb's is neither more nor less than an extinct volcano.

“ About a mile and a half south from St Abb's lies the vil. lage of Coldingham,-northward and westward from which ex. tends the wide moor of the same name, consisting still of greywacke, as far at least as can be determined from its loose rocks and general outline, for few or no fixed rocks make their appearance. It is a wide and desolate region, but far from being uninteresting, especially in cryptogamous botany. The most striking object in this tract is Coldingham Loch, a very curi. ous and beautiful piece of water, about a mile and a half in circumference, and occupying a very deep hollow in the hills. Coldingham is about a mile distant from the sea, to whose banks we shall again proceed, as it is there that the geology of Berwickshire is both the most interesting and the most apparent. Here, and for several miles, the coast appears to consist of alternations of trap rocks, trap-tuff being the most abundant, and the outline of the coast we find accordingly to be considerably broken and rugged. This rock, very similar to that forming the great central mass of Arthựr's Seat, is parti. eularly abundant a little to the north of Eyemouth. Very near this, and forming the bold and projecting point named the Fort, is a very singular and immense bed of conglomerate:

It rests on a rock; which, from its decayed surface, and from being almost always covered with the sea, it is difficult to name, but which has all the appearance a porphyry, or, at all events, of a trap rock. This conglomerate is composed of rolled masses, generally of a considerable size, and from the neighbouring rocks, cemented by calcareous spar. From the appearances at one or two parts of this headland, it would seem that this immense bed is to be considered as the rudi. ments of the old red sandstone formation, there being in these parts several rude, but distinct, attempts at stratification, the rock being there of a much smaller texture; and we believe that a coarse conglomerate of this nature is almost al. ways found accompanying the first formation of old red sandstone.

“ This projecting mass forms one side of the small Bay of Eyemouth, which has evidently been formed by the river Eye, which here empties itself into the sea. On the opposite or eastern side of this bay, the greywacke and greywacke slate again commence, and continue several miles, till we reach the fishing-station of Burnmouth. The greywacke, we may remark, is here very fine grained, being almost entirely felspar. Trap, we may also remark, is here rare, never occurring in greater abundance than as an occasional vein, or thin dike, intersecting the strata ; and wherever this takes place, we almost invariably behold either a distortion or dislocation of these strata.

“ From Burnmouth to Berwick, the sea-banks exhibit a very different set of rocks from any we have hitherto ex. amined. These are the rocks which form the Second or New Red Sandstone Formation, which here present themselves very

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