1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 85 



which is always to be observed over the whole of the area — the sus- 

 pended matter which the water here indicates — alike favour the suppo- 

 sition that the minute particles of matter which could alone find their 

 way to such a distance, could not accumulate at such a place. 



If on such evidence we assume that the whole of the Channel valley 

 had at some former period a higher level than at present, many other 

 anomalies become intelhgible. The banks of the Channel, such as 

 Jones's, have tabular summits, often of rock, whilst the sides are steep, 

 and composed of coarse materials ; they are just such masses as some 

 of the groups of rocks (such as have been already noticed in the 

 vicinity of the Channel Islands, and which have been cut down by 

 the prolonged action of the sea at a given level) would be if let down 

 into fifty fathom water. The summits of all the Channel banks keep 

 nearly the same depth, and would seem to point to some former higher 

 and common level, for their distance from the present surface is such 

 that the sea cannot possibly affect them mechanically. 



In the very coarse beds which form the floor or lowest levels of the 

 Deeps in the upper part of the Channel, from the meridian of Cape 

 la Hague eastward, and which have a depth of forty and fifty fathoms, 

 we also seem to have the highest marginal zone of some former period, 

 over which the drifting beds of the actual period are spreading ; and 

 on the other hand, such masses as Jones's bank are to be considered 

 as protruding portions of an older sea-bed isolated amidst the ooze de- 

 posits of the present sea. 



The data are as yet too few to enable us to determine whether indi- 

 cations of more than one former permanent level can be detected in the 

 characters of these portions of the Channel bed ; but there, is enough to 

 warrant the conclusion, that at certain places former depths must have 

 been different, and apparently less than they are at present, and that 

 one such marginal level existed about the line of fifty to sixty fathoms. 



There is yet a point to be noticed connected with the physical 

 history of the Channel valley, and that is the nature of the rise which 

 takes place at its western extremity, and which serv^es as its boundary 

 with respect to the Atlantic depression. The Little Sole Bank has 

 depths on its eastern side of ninety fathoms ; but this rise is very 

 trifling compared with that which its western slopes present. I have 

 attempted a representation of the outline of this portion of the Chan- 

 nel sea-bed, by the aid of the soundings which have been taken by 

 the French and English surveyors ; and in explanation of it, it may 

 perhaps serve to give a better notion of the extent of inequality of 

 surface here indicated, if I borrow an illustration from the physical 

 features of a well-known district, than to attempt to represent it by 

 sections*. Within a distance from the summits of the Little Sole 

 Bank, not so great as from the top of Snowdon to the sea, soundings 

 have been obtained of 529 fathoms; in other words, the Sole Bank 

 rises from that level to a greater height, and more rapidly, than does 



* Lengthened sections having an approach to a true scale accompanied the 

 paper when read ; these cannot be reduced, and to alter the scale of distances 

 and depths would be to do away with their use. 



