S. JI. Warren — Age of Stone Implements. 101 



implements probably belonged to two distinct epochs. At about 

 eighteen inches from the surface in this clay drift there was what 

 I called a "layer of stones." On sorting out the flints (both 

 worked and unworked) from this layer of stones, according to 

 their mineral condition, I found that they fell into the following 

 classes : — 



A. Abraded and corroded : -Kith a deep brown patina. 



B. Much corroded and abraded; whitened over an earlier ochreous staining. 



jN'ot very abundant. 



C. Somewhat abraded ; commonly mottled with white over a slight ochreous 



staining (red more often than brown or yellow) ; the whole patina very 

 superficial. 



D. Unabraded ; practically unaltered in condition. 



E. Unabraded flint nodules and fragments ; more or less bleached white. 



Implements rare in this condition. 



Leaving class C out of account for the moment, I will proceed to 

 show that while A and B are derived from an earlier drift, D and 

 E are contemporary, or nearly so, with the deposit in which they 

 were embedded. One might hazard a guess that A and B were 

 older than D and E, simply from the fact of their being abraded, 

 corroded, and ochreous in condition, but a more careful examination 

 shows the evidence to be far stronger than this alone would be. 



Many of the flints in condition A and B are found to be broken 

 across, the later fractures being in condition D or E. These 

 specimens, showing fractures of two different ages, are clearly 

 defined from those which show a different condition on their two 

 surfaces through some accident of preservation. Firstly, the later 

 fractures in the former case very rarely occupy exactly one surface 

 of the flint. Sometimes the newer fractures are a mere chip on the 

 edge, sometimes it is a corner of the flint that has been knocked off, 

 or sometimes the flint has been broken up and only a very small 

 surface in the earlier condition remains. Secondly, these later 

 fractures show all round their edges a clear section of the earlier 

 deep patina of the flint : this is the absolute distinction between them. 



Under these conditions, whatever value the difference in age may 

 have, it is demonstrable that the deeper patina is geologically older 

 than the later fracture which crosses it, though this later fracture 

 may also be of geological antiquity. Mr. Worthington G. Smith ^ 

 has figured and described ochreous abraded implements showing 

 later fractures on their edges, and strongly insisted on this proof of 

 their greater antiquity. 



It is, after all, only applying the well-known, and fully admitted, 

 principle in stratigraphy, of discriminating between contemporary 

 and remanie fossils, to the similar problems presented by flint 

 implements. But, undoubtedly, caution and judgment must be 

 exercised in applying the principle. Differences of condition, of the 

 kind that have been pointed out, prove differences of age, but they 

 do not immediately prove that every difference in age belongs to 



1 "Man the Primeval Savage," 1894, p. 216. 



