THE SEVERN TUNNEL. 



53 



encouraged in this by his friend, Mr. Briiton, and by the 

 directors of the Bristol and South Wales Union Railway, 

 who all highly approved of the scheme. It was at this time 

 that ho made the first section across the river with the spirit 

 level ; but before he alludes further to this, it may be 

 of interest that he should describe more fully the natui'e 

 of tliese half-tide rocks, over whicli he had to make the 

 sections. 



The English Stones, before alluded to, are a very remark- 

 able series of indurated beds of new rod sandstone, stretch- 

 ing across the Severn in this place at about half-tide level, 

 and for a distance of about two miles along tlic river. The 

 induration has been such as to luive caused tlio beds in this 

 place to withstand the wearing of the powci'f ul Severn cur- 

 rents, and of the frequent storm waves, for all tlie time the 

 river has run down this course ; while the beds of the same 

 new red formation, a,bovo and below, liave been worn away 

 far below low-water level — out of harm's way, in fact. 

 These hardened strata stretched originally quite across the 

 river from shore to shore, and have been cut througli only in 

 one place — namely, at tlie comparatively narrow and deep 

 channel of the Shoots. The explanation of these facts may 

 bo this : — Looking back to the origin of the luver, after the 

 land had been I'aised above tho sea level, the incipient 

 Severn waters would seek the lowest channel in their way 

 to tho sea, and this channel may at this place have been 

 on the site of the present Shoots cliannel. Now, wiierever 

 this deeper channel was, it must have been subject to wear 

 of a different kind from that applied to what are now the 

 English Stones, and the other collateral rocks, from the fact 

 til at assuming the rise and fall of the tides to be the same as 

 they are now, the strong currents of the spring-tides would 

 then, as now, roll up and down immense quantities of coarse 



