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unexpectedly, and resting apparently without any link or connection whatever, immediately on the greywacke. Of these rocks we shall give a very rapid sketch; but previously to do. ing so, it may perhaps be as well to diverge for a few moments a very little towards the interior, to notice the Hill and Moor of Lamberton, which commence less than half a mile from Burnmouth, and which we remark as the last tract of any consequence, in this direction, appertaining to the Transition series. The high ground now noticed rises almost immediately from the shore to the height of about 300 feet above the sea's level. Generally speaking, it presents a smooth, green outline, with very few projecting rocks. Several small streams produce a variation on its surface, in some places forming narrow ra. vines, in others marshes.* As far as a very moderate examina. tion has gone, it seems fundamentally to be greywacke, with subordinate beds of porphyry and transition granite or sienite ; but from the thick verdure, and 'the want of naked rocks, it would be very difficult, without most minute inspection, to give any thing like a satisfactory account of the geology of this hill. Looking from the slope of these heights, which overlooks the ocean, we observe far below a broad flat terrace, or table. land, presenting a very abrupt face to the sea. This is part of the New Red Sandstone Formation, which, as we have already said, extends along the whole coast from Burnmouth to Bér. wick,-a narrow stripe at first, but gradually increasing in
* RAY seems to have found Tofieldia palustris by the side of that stream which rises on this hill, and runs by the Shields. The ravine above Burnmouth is one of the most interesting botanical resorts in the neighbourhood. The hill itself is rich in plants; and the vast profusion of Funaria hygrometrica and Didymodon purpureum in particular places, is worth remarking.
breadth as we approach the mouth of the Tweed. The princi. pal rocks of this Formation (as it occurs in Berwickshire at least) are sandstone and sandstone slate, indurated marl, a coarse kind of limestone, and thick beds of conglomerate. In general appearance, it bears some resemblance, at first sight, to the Coal Formation ; but is evidently more recent in its date, and more mechanical in its structure. The predominating and characterizing rock is the sandstone, which is soft, friable, and variegated in its colour. The town of Berwick is built on this formation, and, we believe, what are called the Liberties of Berwick, are all included in it. At the mouth of the Tweed, near Berwick Pier, we have an excellent opportu. nity of noticing the characters of this formation, the succession of its rocks, and the disposition of its strata. The principal rock there is still the sandstone, containing numerous impressions, principally of tropical plants.* This formation is continued southward under the bed of the Tweed: at a short distance from which, it is succeeded by the Coal Formation of Northumberland.. -Ascending the course of the Tweed, we behold, for many miles, on each side of the river, a display of nearly the same rocks as those observed at its mouth, sand. stone still being the predominating substance. The sandstone almost always is found forming the bed of the river, the rest of the banks being generally alternations of sandstone slate, indurated marl and conglomerate, the last being of a very recent and mechanical aspect (consisting of the same substances which still compose the channel of the river), and usually occurring highest, although frequently this situation is held by the sandstone. In this sandstone numerous vegetable remains occur, and these occasionally of a great size. In quarrying it, the workmen often come to a harder variety, which they term Bastard Whin; and numerous circular masses of this descrip. tion every where present themselves, which seem very like rolled masses of an older date, which have become accidentally imbedded in their present situation, when the sandstone was forming. Calc sinter is the only other substance worth men. tioning as accompanying this formation, and that both of an ancient and of a modern date.
* The coarse limestone, however, consists almost entirely of bivalve shells, echini, and corallines.
At the distance of a mile or two from Berwick, we notice the mouth of the Whiteadder, a tributary of the Tweed, the banks of which, for nearly half its course, by Edrington, Foul. den, Hutton, Allanton, and Chirnside, exhibit a succession of the self same rocks, except on the banks at Hutton Hall, where we meet with a mineral different from any now noticed, but which, in other parts of the world, sometimes occurs in great abundance in this formation. This is the fibrous gypsum, both the red and white varieties of which occur in the form of numerous thin beds, alternating with the sandstone and marl. Still ascending the Tweed, we pass the fine domain of Paxton, the well-known Chain-bridge a little above it, Norham Castle, Ladykirk, mouth of the Till, and Coldstream regarding all which places it is unnecessary, in an outline of this description, to say more, than that the self-same rocks, with almost the same characters, and nearly in the same suc. cession, still continue to present themselves.
“ Leaving such details, we conclude the present outline with one or two general remarks. The first regards the situation which this formation holds, and the relation which it bears to those by' which it is bounded. On the N. and NE, as al. ready mentioned, it is bounded by the rocks of the transition series, and on the S., a short way beyond the Tweed, by those of the coal formation. It thus occupies a great hollow or basin between these two formations, lying above coal on the south, and apparently resting immediately on grey wacke on the north. On the west it is bounded by rocks belonging to the Old Red Sandstone.
66 The second remark regards the probable date or era of this formation. Lying above the coal formation, it is natural to suppose that it must have been formed at a period subse. quent to that formation, and this conclusion will be strength. ened by an examination of the rocks themselves their more simple, rude and mechanical aspect-their greater softness and looseness the similarity of many of them to deposits still forming, together with the difference of contained organic re. mains-all tending to show that they are newer than the coal formation that they have been formed more rapidly than the rocks of that series, and when the energies of nature do not appear to have been so high.
« Our last remark regards the probability of coal being found in Berwickshire. Various attempts have been made in different parts of the county to discover this important mine. ral, but hitherto without success, although the bores in several places, we believe, have exceeded sixty fathoms. Nor is this surprising. Coal, or at least coal fit for use, is not a member of the New Red Sandstone Formation; and although it is a fact, that, in many parts of England, coal is apparently wrought to a great extent in this formation, yet it is not in any part of it, but in the real coal formation, which lies under, that the coal is found. We do not say, therefore, that coal is not to be found in Berwickshire, as long as we know that it rests towards the south on the coal formation of Northumberland ; but the facts now nientioned, should convince those interested in its discovery, that it is in vain to look for it in any part of that formation which covers the low part of Berwickshirethat this formation must previously be completely dug through -that then it must be ascertained whether the next rock be, or be not, an undoubted member of the coal formation; and that until all this be done, the occurrence of coal in Berwick. shire must be considered, as of all uncertain things, the most uncertain, and the most problematical."
The Nomenclature which I have adopted, unless when the contrary is specified, is the same as that of the “ English Flora” of Sir J. E. SMITH,-a work which stands unrivalled in this country for the purity and accuracy of its descriptions, and for the interest of its botanical discussions. The Arrangement of British Plants by Dr WITHERING, the Flora Scotica of LIGHTFOOT and of Professor HOOKER, the Flora Lapponica, the Flora Edinensis of Dr GREVILLE, the Botanist's Guide through Northumberland and Durham, and the Catalogue of Plants growing in the vicinity of Berwick by Mr THOMPSON, have been regularly consulted, and whatever information they contained suitable to my purpose, has been borrowed without
A considerable number of extracts has been made