III. — Tlie Flint Flakes of LyelTs First Stone Period. — By John" 

 Samuel Enys, F.G-.S, 



Read at the Autumn Meeting, November 15, 1866. 



I PROPOSE, at this Meeting of the Institution, to express my 

 conviction, that Flint Flakes of Ly ell's First Stone Period 

 are natural products, and that they have not been made by the 

 hand of man. 



This conviction respecting their production by natural forces 

 was arrived at during the year 1844, while I was engaged in a 

 comparison of the conditions of the crusliing of quartz in the sub- 

 soil of Mylor Downs, with that of the flint breakage which prevails 

 in the neighbourhood of Eastbourne. 



The Cornish portion of the subject of the deposition of sub- 

 soils seems connected with the formation of tin ground on the 

 bared rocks of the valleys below ; while the flint flakes found in 

 the subsoil of the Wealden, and in similar positions elsewhere, 

 have been said to be the work of man because, it is asserted, no 

 natural causes are known to exist capable of producing flakes of 

 their specific form. 



It is to this assumption I object ; and I would recommend the 

 parties who hold it to try ^nd break flints by any of the following 

 modes : — 



1. By striking one against another. 



2. By crushing them in the ruts of a farm, road by the rolling 

 pressure of the wheels of a loaded manure cart. 



3. By the slower crushing force of a blacksmith's vice. 



I think they will come to the same conclusion as I did in 

 1844 — That the upheaval of the Wealden was accompanied by a 

 compression of the chalk, not unlike that which is found near 

 Freshwater Bay in the Isle of Wight, where chalk flints have been 

 found shattered into sand by a general compression of the beds. 

 Possibly a less degree of force Avould be found necessary to break 

 flints with their usual conchoidal fracture ; but I would advise 



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