Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/106

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96
Mr. Horner on the Brine Springs at Droitwich.

throughout the whole of that extent, and even for some miles to the south of the spot I have just named.

Mr. Aikin observes that the red sandstone of Shropshire does not effervesce with acids: in this respect, therefore, it differs from that of Droitwich, for both varieties of the sandstone effervesce pretty briskly for a short time, but that which is of a grey colour appears to contain the greatest proportion of calcareous matter.

The extensive beds of rock-salt, and the brine-springs of Cheshire, according to Dr. Holland,[1] are situated in strata of a similar nature.

§ 4. The surface soil which covers the red sandstone, contains large pebbles, generally about the size and shape of a goose's egg, but often larger. Those which I examined consisted of compact bluish grey quartz, very much resembling some varieties of flint and chalcedony, and different varieties of coarse and fine-grained quartzose sandstones. These pebbles are not found in great quantity, for, as I was informed by a labourer, they are picked off the surface of the fields for the purpose of mending the roads, no spot having been found in the neighbourhood, where they are sufficiently abundant to pay the expence of digging for them.

§ 5. With regard to the nature of the rocks through which the brine-pits were sunk, I have not been able to obtain any very distinct information, as no new pit has been made for the last thirty years. All that I have in my power to lay before the Society on this subject, is the account contained in Nash's History of Worcestershire, together with some details I received from an inhabitant of Droitwich, who was on the spot at the time the last pit was dug. The following is the information given by Dr. Nash.

  1. Trans. of the Geol. Society, vol. 1, p. 38─See also his Agricultural Survey of Cheshire.