Dr Mitchell on the Chalk and Flint ofYorlcshire. 7S 



to be very great. It is not easily broken into long flakes. It 

 cannot be broken with ease in any direction. On the contrary, 

 the Yorkshire flint is a most unmanageable substance, not easily 

 breaking without great violence, and then the fragments are 

 short, small, and clumsy, and not yielding a graceful form and 

 long sharp edge. It is totally unfit for the gun-flint maker. It 

 can never have supplied knife-blades and kelts to the ancient 

 Britons, and innumerable fragments must have been struck off 

 before any suitable for a spear-head, or the point of an arrow, 

 could have been procured. In a barrow opened near Scarbo- 

 rough, the head of a spear, and the points of arrows, were found 

 along with the skeleton of a chief, and these are to be seen in 

 the Scarborough Museum, and have been described and figured 

 in a publication by Mr Williamson junior. They are as clumsy 

 as it is possible to conceive, and far inferior to what might rea- 

 dily, by the most inexperienced, be struck from the flint found 

 in the south. 



The outside of the Yorkshire flint does not, by exposure to 

 the action of the air and water, acquire the thick white crust 

 which is uniformly produced under similar circumstances, in the 

 flint from chalk in the southern counties, which is often sup- 

 posed, from its appearance, to be a combination of flint and 

 chalk, but which is seldom any thing else but the flint itself. 

 The Yorkshire flint, on exposure, becomes on the outside of a 

 reddish-brown colour, not unlike rust from iron ; but, on the ap- 

 plication of the hammer, it is found to be merely on the very 

 superficies scarcely the thickness of a coat of paint, and below it 

 the flint is unaltered. 



Nodules of pyrites were frequent, which is sometimes, but not 

 often, the case in the south, until we come to the chalk below 

 the flint. 



Altogether, the flint at Flamborough Head bears a great re- 

 semblance to the chert brought from Flintshire to the potteries, 

 in different parts of England, and which is employed for the 

 purpose of grinding the flint found in chalk, after it has been 

 rendered white and friable by being burnt in the fire. 



From observations on the chalk formation in Ireland by Mr 

 Conybeare and Dr Buckland, published in the Geological 

 Transactions, vol. iii. p. 169, 170, it would appear that the 



