302 Mr. R. C. Taylor on the Natural Embankments formed 



The proofs, physical and historical, having been scrutinized 

 with caution, and as Mr. Robberds is pleased to add, with 

 candour, it would appear that the depression of the sea, to the 

 extent assigned, is far from a necessary consequence deduci- 

 ble from that evidence. It has been shown * that the bed of 

 marine shells, at an elevation of 40 feet, alleged to be similar 

 to existing races in our seas, and marking out the line of an 

 ancient beach, belong chiefly to non-existing species, and to 

 the highest in the series of anti-diluvial formations f. The 

 circumstances relating to these testacea, on which much stress 

 was laid, and which pi'obably suggested the first hints whereon 

 to found the hypothesis, not being again adverted to, it is not 

 unfair to infer are abandoned. 



We descend, therefore, at one step to the level of the salinae 

 in the valleys, for there are no intermediate horizontal beds 

 of shells and marine exuviae, which, on the theory of the de- 

 clining waters, must necessarily have occurred and be more 

 or less visible, like the margins of those ancient lakes whose 

 surfaces have progressively fallen by the wearing down of the 

 barriers at their outfall. None of the marshes, at the points 

 where the salinse mentioned in Domesday are conceived to 

 have been situated, are elevated so much above the level of 

 the sea as to be inapplicable to their original purposes, were 

 not the mouths of the aestuary, as I endeavoured to explain, 

 filled up so as to exclude an adequate supply of salt water %. 

 The levels, recently taken by various engineers, prove that 

 the rivers in their progress thence to the ocean have little or 

 no fall: it is well known the marshes for many miles from the 

 sea are below the levels of those rivers ; and in the evidence on 

 this subject before the committee of the House of Commons, 

 it was deposed, that on the occasion of the sea breaking 

 through Lake Lothing, 35 years before, it covered this entire 

 level of marshes to the depth of 3 to 3^ feet with salt water. 



Domesday-book, therefore, would seem to present us with 



* Phil. Mag. and Annals, vol. i. N. Ser. p. 282. 



t An appearance similar to the Bramerton shell bed is repeated on the 

 banks of the Thames, in the great and well-known depository of testaceous 

 remains, 60 feet above the level of that river at Woolwich. Here also ob- 

 servers have not been wanting, to speculate on the apparent subsidence of 

 the waters : yet the same stratum sinks beneath the clay under London, and 

 is intersected in the Tunnel at Rotherhithe, 40 feet below the surface of 

 the Thames. 



J It is not essential to a saltwork that any considerable depth of sea- 

 water should be within command ; the quantity required is uniform, but 

 not large: I believe about 10 inches deep in the reservoirs, and 1 J to 3 

 inches only in the pans. The writer has recently examined, with some 

 interest, the salinae on the Hampshire coast. They are more numerous 

 than on any other part of our shores, and extend from Lymington, west- 

 ward, three or four miles. 



a col- 



