CORRESPONDENCE. 
A NATURAL “EOLITH” FACTORY BENEATH THE THANET 
SAND. 
Str,—A paper by Mr. H. Warren has been published recently by 
the Geological Society (Q.J.G.S., vol. xxv, part 3, No. 303, January, 
1921), entitled ‘““ A Natural © Kolith’ Factory beneath the Thanet 
Sand’, which, in view of the erroneous statements it contains, 
I ask permission to criticize in the pages of the GEOLOGICAL 
Macazine.! Mr. Warren describes a certain series of naturally 
fractured flints found in the Kocene Bullhead Bed at Grays in Essex, 
and proceeds to compare these specimens with others—regarded by 
most archeologists as humanly fashioned—found under totally 
different conditions in various parts of this country. To those who 
take an interest in pre-historic archeology, the occurrence and nature 
of these pressure-fractured Eocene flints, such as Mr. Warren 
discusses, have been known for years past. In 1910 M. lAbbé 
H. Breuil published in [Anthropologie (t. xxi, 1910, pp. 385-408) 
a detailed account of a large series of specimens—similar to those 
found at Grays discovered by him at Belle Assise in France, while 
in 1914 I was able to describe the flaked and broken flints ‘which 
I had found in the Bullhead Bed at Coe’s Pit, Bramford, near 
Ipswich (Proc. Prehis. Soc. of H. Anglia, vol.i, part 4, pp. 897-404). 
It is not my intention to reopen the discussion upon the 
characteristics of these typical examples of flints broken by natural 
pressure, nor again to point out the fundamental differences between 
them and those found by Mr. Harrison upon the plateau of Kent, 
and of others of different forms recorded from the sub-Crag detritus 
bed. I would merely ask those who may regard Mr. Warren’s paper 
seriously to compare the drawings of the specimens found by him 
with those of the Kentian and sub-Crag implements which have 
been illustrated in the publications of various learned societies. 
Such a comparison will at once show the marked differences between 
these shattered and fragmentary Eocene specimens, and the two 
other classes of flaked flints mentioned. I may say that I saw the 
selected material exhibited by Mr. Warren when he read his paper 
before the Geological Society, and I do not hesitate to affirm, with 
a full knowledge of all the facts, that it is preposterous to claim that 
the Grays specimens have any real bearing upon the flints found 
by Mr. Harrison and by myself. And Iam amazed at Mr, Warren’s 
lack of caution in describing, in his paper, such fractured specimens 
as he has found as “‘ Kentish and sub- “Crag forms of chipping’ and 
“Carinate sub-Crag forms of chipping’. ..The publication of such 
statements makes it perfectly clear that he has no real knowledge of 
1 Those who wish to refer to my published opinions upon this question will 
find them set forth in Science Progress, No. 41, July, 1916, pp. 37-50. 
