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greater resistance of the limestones gave the first direction to the form of the 

 valleys as we now see them, though since modified by recent meteoric 

 denudation. This Mr. Mitchell threw out rather for the Club to consider 

 than as being the conclusion arrived at after extended observations. General- 

 izations drawn from a limited area are liable to error, but a speculation is useful 

 as giving direct object for observation, and such considerations for united 

 observations come within the legitimate work of a field club. Should this 

 speculation have any real value it may seriously influence our notions of 

 denudation. 



The President, the Eevds. Preb. Scarth, J. Earle, H. H. Wiuwood, 

 and others took part in the discussion which followed, and raised 

 many objections to the view propounded by Mr. Mitchell. Mr. 

 Win wood hinted at this being rather a revolutionary idea in 

 Geology, and much regretted the compulsory absence of Mr. Moore, 

 who he (Mr. W".) thought would agree with him in saying that 

 Mr. Mitchell's theory depended upon the statement whether the 

 beds of Great Oolite did thin out towards the valleys, and he was 

 inclined to think that such was not an established fact. 



The rest of the evening was spent in a discussion as to the causes of 

 the "headings" seen in most of our Great Oolite quarries. Whether 

 this breaking up of the first five or six feet of the top strata was 

 due to the action of field ice in former times or not — Mr. Mitchell 

 alluding to the question as having been mooted in one of the club- 

 walks — advanced the view that it was the result of water percolating 

 through the stone and then freezing. The nature and results of 

 some experiments which he had lately made on the absorbent 

 power of the Oolites were then communicated to the Club. Having 

 obtained two blocks of stone of equal size — one foot square and one 

 foot six inches deep — he had them hollowed at the top to the depth 

 of about half an inch so as to hold water. In nine days one block 

 of stone had absorbed nearly three quarts of water, while the other 

 block obtained from a different quarry had absorbed scarcely 

 two quarts. This was mentioned as being of interest to builders, but 

 as experiments were not instituted for the purpose of comparing 

 the relative value of the two stones, Mr. Mitchell explained that it 

 would not be fair to come to a rigid conclusion on the subject 

 without further tests. 



The new Greenough Geological Map of England and Wales, which 



