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On some Flint Instruments, and the Geological age of the deposit in which 

 they w&re found upon Stroud Hill. By John Jones. 



Read at Dudley, Juke 17th, 1863. 



One of our Associates, Mr. E. Witchell, of Stroud, having observed 

 during the excavation of a reservoir upon the brow of the hill upon 

 ■which the town stands, that the superficial clay resting upon the Oolite 

 was charged with land and freshwater shells, the writer, at his special 

 invitation, accompanied him to the spot, and deems the observations then 

 made to be of sufficient interest to lay befoi'e the Members of the Cottes- 

 wold Club. 



The space occupied by the Reservoir is partially excavated in the 

 Clypeus bed — the upper member of the Inferior Oolite, — ^the interstices 

 of the rock being puddled with the tenacious clay, by which it was 

 covered before the operations in j^rogi-ess commenced, and which, 

 from the conformable manner in which it has been deposited, is evidently 

 in situ, and must have extended far beyond the edge of the declivity 

 near to which it is now exposed. 



The total thickness of the clays laid bare at this point is from 16 to 

 20 feet, and their elevation above the sea is about 700 feet. A clearer 

 idea of their position and correlation with other beds, than can be 

 conveyed by words, will be obtained by reference to the accompanying 

 plate. 



Upon close examination, we find that the claybank represented as 

 containing shells, flints, (fee, consists of two formations of difierent ages. 



The lower portion is the unfossiHferous retentive clay of the Fullers- 

 earth, by which the percolation of water is arrested, and which forms 

 the true basin of supply for the artificial reservoir now fonning. 



The middle poi-tion, to which we invite special attention, appears at 

 the first glance to be merely a continuation upwards of the last, the 

 argillaceous elements of which it is principally composed, being manifestly 

 the same, and obtained from its disintegration ; but interspersed with a 

 few broken and worn shells of Ostrea acuminata, the characteristic shell 

 of superior beds of the same formation, are found great numbers of land 

 and freshwater shells, belonging to species of Mollusca, which are still 

 common in the district, and which we shall fully enumei-ate with other 

 objects to be described. 



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