ENGLAND. 



713 



)tpth of 

 tnta be- 

 nd coal. 



in Cheshire to Worcester, all the rock salts, and most of 

 the brine springs, are situated. 



Having given this general description of the geology 

 of England, we shall now proceed to a more particular 

 account of it, as well as of its mineral geography. 



What has been denominated the low district of Eng- 

 land, is distinguished, as has been already remarked, by 

 the absence of any regular beds of coal or metallic veins. 

 Chalk, roe-stone, calcareous sandstone, and earthy lime- 

 stone, principally compose it. Eaithy limestone and 

 calcareous sandstone, extend from Dorchester to Nor- 

 thamptonshire, and on the eastern side of Leicestershire, 

 Nottinghamshire, -and Yorkshire, into part of Durham 

 and Northumberland. The earthy limestone in this dis- 

 trict is far from being pure : it is generally of a yellow 

 colour, and some of it contains 20 per cent, of mag- 

 nesia. In the magnesian limestone, there are few orga- 

 nic remains. The strata lie very nearly horizontal, and 

 are, in almost every situation, very distinctly seen. Mag- 

 nesian lime, however, occurs in this district, composed of 

 beds that are singularly contorted and much elevated. 

 Between the chalk and the' limestone, different kinds of 

 calcareous sandstone occur ; the most singular and im- 

 portant, is the oolite or roe-stone, of which the Portland 

 stone, and the Ketton stone of Northamptonshire are 

 varieties. The roe-stone is separated from the chalk by 

 beds of sand and sandstone mixed with clay : these ex- 

 tend with a considerable degree of regularity over the 

 whole of the south-east of England, but vary much in 

 their thickness. It has, however, been remarked, that 

 in the midland and northern counties, less regularity can 

 be distinguished, and that many of the strata, which are 

 distinctly seen in the south, are there entirely missing. 

 Above the chalk, in the low district, lie, in general, thick 

 beds of clay and gravel. In the upper part of this clay, 

 the bones of the elk, the hippopotamus, and the elephant, 

 have been found. In the southern counties, from Dorset- 

 shire to Kent, and in the midland and eastern counties 

 of Wiltshire, Berkshire, Hertfordshire, Buckinghamshire, 

 Essex, Cambridge, Norfolk, Lincoln, and the east riding 

 of Yorkshire, chalk makes its appearance, in different si- 

 tuations, from under the clay. As the general rise of 

 the strata is to the north, as we approach the coal dis- 

 tricts, the strata, which lie under the chalk, rise to the 

 surface. The depth and succession of the strata between 

 the chalk and the coal, have not been ascertained with 

 any degree of minuteness and accuracy, except in one or 

 two plai.-c.v. Mr Townshend, in a work, entitled, " The 

 character of Moses vindicated as an Historian," has given 

 the following as the thickness and succession of the strata 

 from the chalk on the south coast to the coal districts of 

 Somersetshire. Soil and alluvial ground, various thick- 

 ness ; chalk more than 400 feet ; three beds of green, 

 grey, and red sand, with sandstone, 300 feet ; clay 200 

 feet; superior oolite, or roe-stone, 40 feet; calcareous 

 grit, 30 feet; coral rag, 30 feet; forest marble, 40 feet; 

 great oolite, or Bathstone, 140 feet; clay, 140 feet; 

 inferior oolite and sand, 80 feet ; blue clay, 70 feet ; lyas, 

 60 feet ; and red marie, 180 feet. Hence it is probable, 

 thai, allowing for the depth of the stratum of clay over 

 chalk, the depth of the strata in that part of the low 

 district of England, which comprehends the vale of the 

 Thames, to the strata containing coals, will amount to 

 ab'iut 700 yards ; but if we estimate the depth of the ar- 

 gillaceous strata, containing coal, where the chalk termi- 

 aiul the subjacent sand rises from under it, as at 



VOL. VIII. FAKT II. 



Woburn in Bedfordshire, it probably will not amount to Statistics. 

 more than 350 yards. " "" "" 



It has been already remarked, that the mineral pro- Mineral 

 ducts of this district are few and trifling: iron pyrites P r ( J ucts 

 is met with crystallized in some parts of the chalk rocks, tr 

 and crystals of sulphate of barytes, have lately been dis- 

 covered in the pits of fuller's earth near Reegate in Sur- 

 ry. Fuller's earth, also, is peculiar to the strata under 

 chalk. The iron-stone, which is foirtid in part of this 

 district, is not so rich as to bear the expence of bring- 

 ing fuel from a distance to smelt it. The bones of qua- 

 drupeds, already mentioned, are never found in the stra- 

 ta below the chalk, but always in the clay over the 

 chalk. 



The middle district of England, in a mineralogical Middle ilis. 

 and geological point of view, which is bounded on the stri .^" 

 east by the calcareous range that extends from Dorset- 

 shire to Yorkshire ; and on the west from Northumber- 

 land to Derbyshire, by the metalliferous limestone moun- 

 tains of the northern alpine district, or by mountains 

 of millstone grit, resting upon limestone, consists of ar- 

 gillaceous and silicious sandstone. The secondary stra- Secondary 

 ta of this district extend west, till they touch the stratlu 

 Irisii sea, on the coast of Lancashire ; or, farther south, 

 are bounded by the alpine districts of Wales and Devon- 

 shire. The strata here are very irregular, hills of transi- 

 tion and basaltic rocks rising through them, and branches 

 from the mountains of Wales, shooting, as it were, into 

 this district, especially in Shropshire, and in a line 

 extending from that county to the hills of Charnwood 

 forest in Leicestershire. Basalt, or whinstone, also ap- 

 pears in this district, in the eastern moorlands of York- 

 shire, which forms the highest part of it : the sides of 

 the hills composing these moorlands, are covered with 

 a bed of aluminous schistus, upwards of 100 yards in 

 thickness ; this schistus forms cliffs, extending in a wa- 

 ving line along the coast near Whitby : above it lie 

 vegetable soils of various thickness : loose stone or rub- 

 ble of uncertain thickness : coal from four to eight inches 

 thick : compact iron stone, 24 inches thick, and broken 

 iron stone five inches thick. 



The principal coal fields, in the northern part of this Coal fields 

 district, lie in Northumberland and Durham, the west m ils nortl1 - 

 riding of Yorkshire, and Derbyshire : the strata of coal e ^ 

 terminate a few miles to the north-east of the town of 

 Derby, but make their appearance again to the south of 

 the Trent in Leicestershire, near Ashbey de la Zouch : 

 on the south-east, they terminate at the Charnwood 

 hills; while, on the south-west, a thick bed of coarse 

 breccia and gravel, separate them fro'm the coal fields in 

 the county of Warwick. A considerable part of the Red sand- 

 western side of the middle district, from the southern stonc rock ' 

 division of Lancashire to Somersetshire, is occupied 

 by a red sand rock ; which extends through part of the 

 counties of Lancashire, Cheshire, Staffordshire, Shrop- 

 shire, and Worcestershire : the southern extremity of this 

 rock, in Shropshire, rests on highly elevated strata of 

 grey wacke ; and it is probable that if rests, through its 

 whole extent, on transition rocks. No coal is found un- 

 der the sand rock, and it seems to cut off the coal fields, 

 which lie near, or upon it : it occurs at a very low com- 

 parative elevation. The principal salt springs, am! the 

 rock salt of Cheshire, are near, or on the red sand rock, 

 in the vicinity of a range of lofty hills, which extend 

 from the high peak in Derbyshire to Browngrove 

 Lickey in Worcestershire. Near Northwich, in Cheshire , 

 4x 



