the London and Hampshire Basins, 371 



flint and rubble near Dorking (spoken of in a former part of this 

 paper), and the other an immense deposit of stiff loam traversed 

 in part by the Merstham-tunnel. Again_, much debris from all 

 the surrounding beds is lodged in the Peasemarsh valley, appa- 

 rently favoured by the position of that valley after its earlier exca- 

 vation; so the great accumulation of strong and fertile loams which 

 make the hop-gardens of Farnham*, might have been brought 

 from all directions, — out of the gullies at Alton f, along the 

 valley of the gault at Bentley, or down from the rear of the Hogs- 

 back ; perhaps from all of these sources. Cross-currents have 

 mixed the sandstones of the lower greensand beds with the 

 upper at EittleworthJ and at Peasemarsh; and much rubble 

 from the former of these has rushed out on the latter through 

 the transverse gullies (north and south) between Petworth and 

 Thakcham§. These instances might be multiplied, and much 

 more might be said about the range and the other phsenomena 

 of drift ; but it all comes to the conclusion which I drew- from 

 these appearances in my earliest essay on this subject, that '^^to 

 the eye of the practised observer the Weald valley presents the 

 appearance of a great water-channel after a flood : — some parts of 

 it clean and clear of all incumbrance, others loaded with drift ; 

 the banks in some parts torn clean away, in others heaped up 

 with rubbish || ;" and, to make the parallel more complete, in the 

 drift of both are to be found the bones or the bodies of animals 

 that have perished in their several catastrophes. 



It is proper for the completion of this sketch to say a few 

 words about the " Bassin du Bas Bouionnais,^^ as the French 

 call the eastern extremity of the Weald denudation. Mr. Hop- 

 kins has described the signs of upheaval it exhibits correspond- 

 ingly with the phsenomena of like kind on this side of the chan- 

 nel^!. I have enjoyed two opportunities of a cursory inspection 

 of the country, but cannot speak of it critically. M. Bozet has 

 described its diluvium**, which only differs from that of the 

 Weald in having a larger admixture of materials derived from 

 the wreck of the tertiaries, and particularly the fragments of the 

 millstones or '' burrstones " of those beds, which we may suppose 

 correspond in position with our Druid stones or grey-wethers. 

 And M. Bozet considers the denudation of the Boulogne country 

 as the work of the same '^ debacle '' that excavated the Weald. 



* Surrey. f Hants. % Sussex. § Sussex. 



II Geol. Memoir of Western Sussex, p. 84. London, 1828. 

 If Vide Geol. Trans, vol. vii. 

 ** Description Geognostique du Bas Boulonnais. Paris, 1828, 



