204 KELIQULE AQUITANIC^l. 



Both neat and rough flakes, however, tell their own history, as design must be 

 concerned in their formation ; and hundreds may have often been struck off 

 " cores " of flint in some stations (or places where the old Elint-folk lived, or at 

 least manufactured their implements) and allowed to lie about, whilst but few, 

 perhaps, were selected as being of the right shape for the purpose intended, 

 whether used in their original shape or further trimmed by flakings and chippings 

 of edges or ends. 



Again, pebbles of flint and large flake-like pieces may be, and have been, 

 " dressed " into definite shapes as hammers, tomahawks, axes, wedges, chisels, 

 knives, scrapers, and heads of spears, lances, javelins, harpoons, and arrows by 

 careful removal of flakes and chips by repeated and well-directed blows of varying 

 force, chiefly along the intended edges of the instrument. The peculiar fracture 

 of flint (flaky, but showing everywhere a tendency to the " conchoidal " condition, 

 with concavo-convex surfaces) allows of this procedure, and indeed has led to its 

 being done, as is the case with obsidian also. The reiterated blows in definite 

 directions, removing flakes more or less parallel, and resulting in a nearly symme- 

 trical, more or less convex surface, are as plainly traceable as if they had been 

 given under our own eyes ; and the resulting surfaces are very different, when 

 carefully examined, from what occurs on any much-broken or many-faced flint on 

 the beach or in a gravel heap. 



The strong curvatures on flakes of flint and obsidian broken off by smart blows, 

 culminate in what is termed the "bulb of percussion," and, with the correspond- 

 ing conchoidal hollows on the " cores," are of rare occurrence in the naturally 

 broken stones; and hence they are good tokens of human workmanship*. 



A further development of the conchoidal fracture is seen in the cones produced 

 by direct blows on some solid flints. Circular and semicircular concentric flaking 

 is produced by such blows ; these overlapping flakes flying off, a solid cone remains. 

 The battering of shingle on the beach produces such minute concentric flakings by 

 the innumerable blows of pebble on pebble ; and, by the easy removal of the thin 

 edges of the little circular flakes coating the minute cones, the rolling wears the 

 pebbles round. 



Broken flint, exposed to the weather, to water, or to moisture under ground, 

 suffers certain changes of surface. If dark-coloured, it loses its uniform tint and 

 translucency, becoming opaque and either blotched or wholly white or yellow ; if 



* One of the newly invented stone-breaking machines chips small fragments from the rough blocks by 

 direct blows, without crushing ; hence road-metal prepared by such a machine consists largely of fake-chip 

 having bulbs of percussion. EDIT. HEL. AQ. 1873. 



