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THE NEW YORK PUBLIC LIBRARY

ASTOR, LENOX TILDEN FOUNDATIONS

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ON THE

SALT SPRINGS OF WORCESTERSHIRE.*

BY CHARLES HASTINGS, M. D., F. G. S.

AMONG the various objects which engage the attention of the members of the Worcestershire Natural History Society, none seem more important than those which relate to the local history of the county, and accordingly one of the chief purposes for which this Society was formed, was to investigate the Natural History of the county, and to point out its relation to the comforts, the health, the wealth, and the commercial resources of the community.

The brine springs of the county, in this point of view, are more especially an object of great interest. They are of high antiquity, as being sources of much personal wealth to individuals, and of great convenience to the inhabitants of this county generally. The production of salt, moreover, has been of importance to governments, as from the earliest times it has been made to yield to them a revenue by taxation.

I need not here dwell on the manifest reflection that salt is of indispensable utility to man, and that its existence in such rich abundance in the natural world is one of those innumerable proofs of design with which the creation teems. The waters of the ocean yield salt abundantly by evaporation; but the distance of the sea from many localities in which man has pitched his tent, and formed communities of living beings, would manifestly be a great obstacle to the general diffusion of this necessary commodity, if Nature, ever kind, had not buried this treasure also, in the rich storehouse of many of man's possessions-the earth. To this storehouse the intelligence with which he is endowed enables him to have access, and to convert the materials there found to his advantage and profit.

Salt is found in the earth in a solid state, and is hence called rock-salt. The instances are numerous, and the study of the geological connections of salt with its associated rocks, will amply repay any one who takes an interest in the works of nature. Gypsum, or sulphate of lime, and rock-salt are the most valuable minerals found in the secondary strata, and it is from these that most of the important salt springs issue. Now what are the known relations between the production of salt, and the mineral strata in this county ?

On the western boundary of Worcestershire, we have the older rocks, viz. the primitive chain of Malvern and the transition

*A Lecture delivered before the members of the Worcestershire Natural History Society.

July, 1835.-VOL. II. NO. XII.

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rocks of Cradley, Martley, and Abberley; then again on its northern limit, a similar class of rocks is found, and we have also the Coal measures at Dudley; the Trap rocks of the Clent Hills, the Basalt at Rowley, and the Quartz rock at Bromsgrove.* But the formation which most extensively prevails, and of which the county generally may be described as consisting, is the Red Marl, or New Red Sandstone, which geologists consider as having been formed by the breaking up and disintegration of the older rocks before mentioned, and their subsequent deposition from the waters of the ocean.

In England, the Red Marl or New Red Sandstone is a very extensive deposit, stretching with very little interruption from the northern bank of the Tees, in Durham, to the southern coast of Devonshire. Its texture is very various. It appears sometimes as a reddish marl or clay, sometimes as a sandstone; sometimes the clay or sandstone are interstratified, or pass the one into the other; and it will further appear that it is associated with, or contains beds of a conglomerate, consisting of masses of different rocks, cemented by marl or sand. When this deposit appears as a sandstone, its characters differ greatly in different places; it is occasionally calcareous, and sometimes of a slaty texture. Above all, this extensive deposit is remarkable for containing masses or beds of gypsum; and the great rock-salt formation of England occurs within it, or is subordinate to it. In some places the strata of coal dip below it. Generally speaking, the red marl containing gypsum is found in the higher, the sandstone in the central, and the conglomerate in the lower portions of this deposit.+

In Worcestershire, this formation begins at the very northern boundary of the county, and spreads itself over the whole of the district, so that setting out from Stourbridge, and walking directly south to Longdon Heath, below Upton, we are continually passing over Red Marl and New Red Sandstone, for the most part hidden from our view by the beds of gravel which abound so extensively in this line of country. In many parts, however, the sandstone is exposed, and forms pleasing rising eminences, and in some situations there are more elevated strata, in the sandstone hills about Bewdley and Kidderminster. Mr. Murchison has lately read a paper to the Geological Society, in which he takes a view of the New Red Sandstone which occurs in parts of Salop, Stafford, and Worcester; and as the formations which have usually been classed under this term present various appearances, he proposes to divide the group into distinct subformations, adopting the following subdivisions:1st. Red and Green Marl.

2nd. Sandstone and Conglomerates.

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* A complete description of these Transition Rocks, and of many organic remains found in them, not previously known to naturalists, will be given by Mr. Murchison in his splendid work on the subject, which will shortly be published. † See Conybeare and Phillips's Geology, p. 279.

3rd. Calcareous Conglomerates.

4th. Lower Red Sandstone.

I proceed now to point out the different parts of Worcestershire where these subdivisions of the New Red Sandstone formation may be observed, and I shall begin with the lowest of the series, the Lower Red Sandstone. We have this shewn where the sandstone flanks the Malvern, Berrow, and Abberley Hills. It has the character of a conglomerate, in which are imbedded portions of Quartz and the older Trap rocks. Rosebury Hill, near Knightsford Bridge, is a rock of this kind, which is very characteristic. These Red Sandstone Conglomerates in the neighbourhood of the transition rocks, are, therefore, the lowest of the deposited beds of the New Red. Sandstone in this county.

2ndly. Calcareous Conglomerates. There is a well developed calcareous conglomerate zone, lying above that just described, and which is largely and beautifully exposed on the eastern faces of the Clent Hills. The chief imbedded fragments are of limestone, and they are largely burnt for lime to the east of the Lickey and Clent Hills, where they are of irregular thicknesses. These strata are repeated between Kidderminster and Bridgnorth.

3rd. Red Sandstone and Conglomerates. In parts of Worcestershire where the pure sandy beds prevail, particularly north and south of Kidderminster and about Bewdley, there are large districts of rye land, which gives to the agriculture in these situations a peculiarity that must strike the most casual observer. These beds, which are in some parts very thick, may be emphatically called Red Sandstone. We may observe sections of them near Kidderminster and Bewdley, at Hartlebury, near Ombersley, Witley, and Martley. The direction of this division of the sandstone formation is south-westerly.

4th. The Red and Green Marls are met with in another division of the county, commencing to the north of Droitwich, and continuing in a line to Worcester, to the Old Hills, to Severn Stoke, and to Upton; thus running nearly parallel to the former subdivision.

Here then we come to the upper group of the great system of newer Red Sandstone, which more properly may be considered as red marl; associated with which is the bed of rock-salt, extending beneath it, and the brine springs in connexion with it. The prevailing rock around Droitwich appears to be a fine grained calcareo-argillaceous marl, but it is so ill laid bare and is so little exposed, that the composition of the strata generally is not readily ascertained. Sections of it may, however, be observed at the entrance to Droitwich from Worcester; immediately out of Droitwich on the Hanbury road; near the turnpike on the road to Kidderminster; at Dodderhill; and at Brier Mill, near Westwood. It varies greatly in all these places-1st, from

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