Proceedings of the Berwickshire Naturalists' Club.

Date:
[1858]
Catalogue details

Licence: Public Domain Mark

Credit: Proceedings of the Berwickshire Naturalists' Club. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    organisms, its mineral composition and picturesque appear- ance. It is 30 feet in thickness, and being very hard, resists more effectively, than the other rocks, the destructive action of the sea. Resting, however, on a soft shale which is easily broken up and washed away by the tides, this superincumbent limestone is deprived of support, and time after time, large masses tumble down from the cliff into the sea. It now forms a narrow point running into the sea about one quarter of a mile; but the tides and high seas are still working away the lower and softer beds, which connect this pro- montory with the land, and in the course of a few centuries it will become an island on the flow of every tide. This limestone is of a buff colour and generally of a crystalline structure. It is a magnesian limestone, being composed of carbonate of magnesia and carbonate of lime. Besides con- taining Productus giganteus and other commoner mountain limestone fossils, there abound in it large masses of the corals Lithostrotion basaltiforme and Choetetes septosus; and occasionally we find Syringopora ramulosu, which is a rare coral in the Northumberland beds. These distinctive organisms are excellent guides in tracing the range of this sill; northward I have found it at Holy Island, and south- ward 1 have traced it to Spittleford, near to Embleton, and thence to Dunstan, Craster, and Shilbottle; and thence in a south-west direction to Whittle, Newton-on-the-Moor, Fram- lington, and across the Coquet to Ward’s Hill and Rothley. It should be noticed, that the magnesian character of this limestone is a local phenomenon, and seems in some way to arise from its neighbourhood to basalt. In several parts of its range, as at Shilbottle and Framlington, it is a compara- tively pure carbonate of lime. There are eighteen different coal seams in the section ; most of them are thin and of an inferior quality, none, excepting two, exceeding 2 feet in thickness, and their aggregate thickness is only 24 feet 4 inches. That which is called the Beadnell coal (number 35 of the section) has been worked both for domestic use and for burning lime. It is of variable thickness, seldom less than 2 feet 6 inches, and generally about 3 feet; but on Mrs. Taylor’s estate, it has been found as much as 6 feet thick, and of a better quality than in other localities. It lies there, however, below the sea level; and as the sea sometime ago broke into a neighbouring colliery, due precautions would be necessary, to prevent a similar irrup- tion, in the event of this more valuable portion of the coal seam being worked for the use of the district.