THE GEOLOGIST 



DECEMBER, 1860. 



THE GEOLOaY OF THE SEVERN VALLEY RAILWAY. 



A SKETCH BY 



GEORGE E. ROBERTS. 

 AUTHOR OP "The Rocks oe Worcestershire." 



Deep cuttings and long tunnels are regarded by railway-contractors 

 as things to be avoided, tbougb lessons of tbe greatest instruction 

 are derived from tbem by the student of geology. But as safety in 

 transit demands the easiest gradients, and a line as straight as pos- 

 sible, the lesser inequalities of the surface have often to be cut into, 

 so that no insignificant part of geological teaching is derived from 

 railway- work. And oft-times a way that puzzles the contractor to 

 make " good," or a hill-slope that, lacking knowledge of its springs, 

 he has cut into only to see it slip continuously upon his line, are 

 great aids and helps to comprehending the natural formation of a 

 district, and so, a contractor's poison becomes a geologist's meat. 



There are many such instructive points upon the Bridgnorth rail- 

 way, which after briefly noting I hope will be looked at with pleasure 

 by observers. In the mere name of the line there is a certain spice 

 of geology' — " The Severn Valley its whole course being along a 

 narrow and in places deep valley, scooped out like a channel between 

 England and Wales. Perhaps everyone knows that at no very dis- 

 tant time, the tide which now laves the beaches of Cheshire, came 

 rolling down this arm of the Irish sea, bringing shoal sand, and 

 banking it in places about its course, and rolling the pebbles along 

 its current till beaches, as well marked as those of Rhyl and Llan- 

 dudno, were laid in lines parallel with the flow. Everybody sees 

 evidence of this in the gravel-beds which lie upon the red sandstone 

 in so many places, in these border- counties, and specially to be noted 

 in the neighbourhood of Bridgnorth, at Acleton and Worfield, where 

 Terehroe, those slender trumpet-shells so abundant on the Welsh 

 coast, may be picked up in sand ; at the Knowl — more firm sand, by 



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