42 



CONGLOMERATES OF RED SANDSTONE. 



them, being nearly free from mica, with occcasional partings of brown slightly mica- 

 ceous marl. Some of the lamina? are filled with very minute grains of coal derived 

 from the adjacent fields, the whole reposing on the calcareous conglomerates of Horsley 

 Bank, which belong to a subjacent part of the system. (See PI. 30. fig. 8.) 



In Worcestershire, as in Shropshire and Cheshire, the Saliferous Marls underlie the 

 Lias, and pass downwards into larger masses of sandstone which rise at a very gentle 

 inclination into hills west of Droitwich, and extend to Ombersley and Hartlebury, where 

 the rock is a finely grained, argillaceous sandstone, slightly calcareous in parts, of a dull 

 red colour, with, occasionally, spots of green, blue and white. The sandstone in the 

 adjacent parts of this district (Bromsgrove, &c.) agrees so closely, that it is unnecessary 

 to repeat the description of it at other localities in Worcestershire. Besides, the tract, 

 is for the most part so much covered with gravel, as to render it difficult to assign 

 precise geographical boundaries to this subdivision. 



In the tract between Kidderminster and the Clent Hills, in the hills surrounding the 

 Dudley coal-field, and again in the district ranging far to the north in Staffordshire, 

 the central sandstones contain beds of conglomerate, chiefly filled with rounded pebbles 

 of quartz rock \ The pebbles vary in dimensions from the size of a child's head to 

 that of an almond, consisting chiefly of white and pink quartz, with others of Silurian 

 rocks and Old Red Sandstone ; the whole subordinate to, and inosculating with thick 

 beds of deep Red Sandstone. The quartzose conglomerates occupy a great number of 

 hills, the surfaces of which are usually much disintegrated, and hence they have 

 afforded much of that detritus which has been spread over so large a part of the low 

 country of Worcestershire and around the Clent and Lickey Hills. (See the conclud- 

 ding chapter on Gravel.) Numberless sections, however, expose these rounded quartz 

 pebbles, imbedded in the Red Sandstone at different localities over an immense area, 

 extending by Wolverhampton to Cannock Chase, and spreading from Birmingham on 

 the east, to near Bridgenorth on the west, and thence into North Salop ; but detailed 

 sections of quarries, in which nearly all the materials are alike, whether near the Bar 

 Beacon, at Himley, Wolverhampton, or at Hodnet, would only fatigue the reader and 

 convey no real instruction. In some situations, the uniform character of these conglo- 

 merates is varied by the addition of a few pebbles and fragments of the Cambrian, Silu- 

 rian, and Carboniferous systems, including trap rocks. Instances of this sort occur 

 between Bridgenorth and Wolverhampton, but it is doubtful whether some of these 

 beds may not rather be classed in the inferior divisions of the New Red System. 

 There is a prodigious accumulation of quartz pebbles, resulting from decomposed New 

 Red Sandstone, at Wallsall, where they cover indiscriminately Silurian limestones, and 

 coal measures ; indeed, in this and many other parts of the coal-field of Staffordshire, 



i Good sections of these beds are exposed on the sides of the road from Stourbridge to Kidderminster. In 

 some of the red sandstones near the Lickey, grains of black oxide of manganese are disseminated, as in the 

 sandstones of Shropshire, (p. 38.) 



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