EVIDENCE DERIVABLE FROM THE FLINTS THEMSELVES. 277 



Mr. Prestwich : " It was lying flat in the gravel at a depth of 

 seventeen feet from the original surface, and six and a half 

 from the chalk. One side slightly projected. The gravel 

 around was undisturbed, and presented its usual perpendicular 

 face. I carefully examined the specimen, and saw no reason 

 to doubt that it was in its natural position, for the gravel is 

 generally so loose, that a blow with a pick disturbs and brings 

 it down for some way around ; and the matrix is too little 

 adhesive to admit of its being built up again as before with the 



same materials I found also afterwards, on taking out the 



flint, that it was the thinnest side which projected, the other 

 side being less finished and much thicker/'* But evidence of 

 this nature, though interesting, is unnecessary ; the flints speak 

 for themselves. Those which have lain in siliceous or chalky 

 sands are more or less polished and have a beautiful glossiness 

 * of surface, very unlike that of a newly-broken flint. In 

 ochreous sand, "especially if argillaceous, they are stained 

 yellow, whilst in ferruginous sands and clays they assume a 

 brown colour," and in some beds they become white and 

 porcelanous. In many cases, moreover, they have incrusta- 

 tions of carbonate of lime and small dendritic markings. 

 Freshly-broken chalk flints, on the contrary, are of a dull 

 black or leaden color ; they vary a little in darkness but not 

 in color, and do not present white or yellow faces ; moreover, 

 the new surfaces are dead, and want the glossiness of those 

 which have been long exposed. It is almost unnecessary to 

 say, that they have no dendritic markings, nor are they 

 incrusted by carbonate of lime. 



Now the forgeries for there are forgeries differ from the 

 genuine implements by just those characters which distinguish 

 newly-broken flints from those which have lain long in sand 

 or gravel, or exposed to atmospheric agencies. They are 

 black ; never white or yellow ; their surfaces are not glossy, 

 * Phil. Trans. I860, p. 292. 



