221 
“ One of these, two and three-quarters inches long, has been 
chipped or jagged along one edge, apparently by use, while the 
broad round end is so much worn away as almost to assume 
the appearance of a scraper. Most of them bear decided 
marks, either on their sides or ends, of having been in use as 
scraping tools.”* 
The answer to this kind of evidence is obvious and clear. 
The flakes struck off at a single blow by the flint-knappers of 
Brandon often show this jagged edge as the result of the natural 
fracture, and the side of a gun flint trimmed by one stroke of 
the hammer presents this appearance of minute chipping. 
Again, a flake carried forward in a melee of gravel, must have 
its delicate edge broken and chipped in places ; most of the 
subsoil flakes are notched in this manner, and so are the thin 
edges of the roughly-broken flints found with them ; indeed it 
is so obvious that the jagged edge is the result of natural causes, 
that MacEnery adduces this point as a mark of distinction 
between the rubbed flakes found in sepulchral urns m the 
Barrows, and the flakes from the Caverns; he says ‘ ‘None 
of the cavern blades appear to have been rubbed or polished, 
but exhibit the rough serrated edge of the original fracture ”+ 
This jagged edge of the flake naturally results from the 
manner in which flint fractures. When the conchoidal side of 
a flake is carefully examined under a glass, it will be seen that 
segmental wave-markings curve around the bulb of percussion, 
and, like the undulation of water from the fall of a stone, the 
crest of the wave is somewhat higher than the trough ; and thus, 
as the wave runs out to the edge of the flake, the greater thick- 
ness and strength of the crest produces a point, and the trough 
forms a notch. It is, of course, only on some flakes that this 
effect can be observed, as other causes have operated to blunt 
or break their edges. 
Thus, this newly-invented evidence of use is not only altogether 
different from that impressed on the recognized stone imple- 
ments, but it is obviously the result of natural causes. 
We have now to examine the evidence on which the great anti- 
quity of the “ flint knives ” found in the gravel and loam of the 
Cavern has been attempted to be proved. On this point I will 
give the statement made by Mr. Pengelly at a joint meeting of 
the Archaeological and Ethnological Societies, on the 19th of 
Eebruary, 1861. I quote from the Geologist , the. editor of 
which says: a Mr. Pengelly made such very important 
remarks on the Brixham Cavern that we give his speech in 
full” He said : “ There was a remarkable circumstance con- 
* Ancient Stone Implements, p. 471. 
f Cavern Researches, p, 7(\ 
