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had been thrown up long before an atom of tlie secondary rocks had 

 been deposited against them, from their greater compactness and 

 durability, presented materials better calculated to resist water action 

 than the softer Oolite rocks, when brought into operation with equal force 

 upon both, which must have been the case, and would therefore tend 

 to the much more rapid disintegration of the latter. This must be 

 apparent when we take into consideration the fact that, from want of 

 exposure to the sun, these could not have been hardened and consolidated 

 as we know them ; for it is only by complete and lengthened exposure 

 that they even now become weather proof. Supposing the most constant 

 direction of the winds and tides to have been the same as at present, 

 which the conformation of the excavated valley goes to show, the 

 erosive force would be principally upon the softer rocks, leaving the 

 harder compai'atively intact. That this was so, we may gather from the 

 fact that the heads of most of the combes here are in the direction of the 

 N.N.E., according with that of the tides, strengthened by the stUl 

 prevailing W.S.W. winds, the currents being thrown off, moreover, in 

 the same direction from the spurs of the older hills, and producing 

 corresponding depressions in those of the secondary fonnation. 



Thus we find the old limestone rocks thrown up at acute angles, 

 as ramparts around the coal formation, and preserving the measures 

 within them little abraded, whilst the clays and shales above the coal 

 have been greatly denuded, and form what may properly be called 

 basins within them. A glance at the map and sections proves this. 



That its course may have been modified or influenced by analogous 

 circumstances, in its upper portions, seems more than probable, but this 

 fact, for want of positive personal knowledge, we remit for future 

 verification. Are there no circumstances to show that the perpendicular 

 cliffs of Westbury, Wainload, and the Mythe, are comparitively modem 

 faults 1 but of the occurrence of these we may have to speak hei'eafter in 

 the promised paper. As the lake period is j^resumed to have contributed 

 to our local geology the great bulk of the oolitic gravels, which, with their 

 interesting contents, strew the vale of Evesham, Gloucester, and Berkeley, 

 wc shall briefly mention, in connection with these, a fact wliich has come 

 to our knowledge, within the last week, communicated, like that which 

 hea<Ls the paper, by Mr. Witchell, whose acuteness of observation, 

 assiduity in collecting facts, and liberality in imparting them, since he has 

 commenced the study of geology, are entitled to the highest credit. The 

 oolitic gravel in question is too well known to require here any particular 

 description, it will therefore be sufiicieut for our i)urpose to remind you 

 that along the sides of the Cotteswolds, in addition to fossils fitjm almost 



