APPENDIX. 



375 



are described in Chaps. XVI. and XVII. The basalt dyke of Cleve- 

 land, which runs through the North Riding of Yorkshire into Dur- 

 ham, is described, with other basaltic rocks in England, in Chap. IX., 

 and the alluvial beds, marked 111, are described in Chap. XXI. A 

 description of many of the mining districts of England and Wales will 

 be found in the chapter on metalUc veins. 



It now remains to notice the sections in different parts of England. 

 A seetion, to possess much value, should be made as nearly as possi- 

 ble along the true hne of the dip and rise of the strata. W^e possess 

 no true line of dip in England, which passes through all the different 

 classes of rock ; and it is only misleading the reader, to represent the 

 succession of rocks out of their true situation. The section of the 

 secondary strata, with a small portion of the tertiary, given at page 

 160, represents the succession of the different secondary formations, 

 from chalk to the lowest new red sandstone, taken in a line from the 

 chalk hills north-west of London, to the transition rocks south of the 

 Malvern HiJls, in Herefordshire. But in this line, the lower red 

 sandstone, and magnesian limestone are wanting. 



If we draw another line across England, through Durham and 

 Cumberland, from the German Ocean, near Sunderland, to the Irish 

 Channel, (see section, Plate VII.) we may observe the magnesian lime- 

 stone A forms the uppermost rock of the series ; all the secondary 

 strata above this formation are here wanting ; it is, however, proba- 

 ble that they may once have extended into the German Ocean, in the 

 order represented at page 160. The magnesian limestone a lies un- 

 conformably upon the coal strata, which rise to the west b b ; at x the 

 strata are broken by the Burtreeford Basalt Dyke, c c represents the 

 lower beds of the coal strata, with mountain limestone ; they termin- 

 ate at the mountain called Gross Fell, 5. The lower part of this moun- 

 tain is composed of mountain limestone and greywacke ; a little to the 

 west, the beds are broken, by nearly vertical beds of trap and sienite. 

 In the Vale of Eden is Penrith Beacon, 4. This vale is covered by 

 beds of conglomerate and red sandstone. The lofty mountains, e e, 

 that surround the lakes of Cumberland and W^estmoreland, are skirted 

 by beds of mountain limestone ; but the higher mountains are chiefly 

 composed of slate, felspar, porphyry, and greywacke. Granite oc- 

 curs at the base of Skiddaw and Saddleback, and at Coldback Fell. 

 1, is Sea Fell, the highest mountain in this group ; 2, Skiddaw ; and 

 3, Helvellyn. Farther west we come upon the coal strata of V^hite- 

 haven, dipping west, and covered by unconformable secondary strata. 

 Some of the more remarkable rocks in the mountains round the lakes 

 are described in Chap. VII. Plate II. fig. 4, represents the arrange- 

 ment of the strata in the central part of England, passing in a line 

 nearly east and west, through the low granite range at Charnwood 

 Forest, in Leicestershire : e, on the right-hand side of the plate, rep- 

 resents lias resting on red marl and sandstone, a. The granite and 

 slate rocks are represented, b b c c, partly covered by horizontal beds 

 of red marl and sandstone : d d are the coal strata, near Whitwick, 

 much elevated as they approach the Forest Hills. A little out of the 

 line of section, are represented the elevated beds of mountain lime- 

 stone at Breedon and Clouds Hill, part of which limestone is eontin- 



