92 NATURAL SCIENCE. February, 1897. 



this interesting specimen ? I am fully aware of the fact that 

 implements ought to be seen before one passes an opinion upon them ; 

 and I am equally conscious that before one can determine the 

 possibilities of natural forces, and distinguish them from man's work, 

 one should have years of actual and practical experience — not so much 

 in rummaging amongst second-hand collections, nor even in visiting 

 pits and buying implements from workmen, but in making them one- 

 self. When one understands so much of the working of flint as to be 

 able to set out and make an implement of any pattern and style of 

 work desired, and also is able to tell a modern forgery at sight, then 

 ■one is qualified to say what man or nature can or cannot do. In the 

 eye of such a one as this, I am certain that the present specimen 

 would improve upon acquaintance. 



Fig. 3 shows a worked bulbed flake from the same bed as no. i. 

 It is one of the purple-black specimens. Only a very small portion 

 of the original surface remains. The removed flakes in all cases were 

 detached by sharp well-directed blows administered from the bulb- 

 face, and frequently took a clean sharp direction quite across the flint, 

 and when physically possible always show conchoidal ripplings and 

 pits of concussion. It is this secondary flaking which gives rise to 

 the present outline : only a very small portion of the original unworked 

 surface of the flint remains. This specimen shows a well-marked 

 evaillure, the meaning and importance of which must be explained at 

 greater length. 



I have tried some thousands of experiments of fixing flints and 

 pitching round pebbles at them, and thus removing flakes, also by 

 special suspension arrangements I am able to administer any number 

 of blows at any particular spot with various degrees of force ; but I 

 have never yet been able to produce this scar in any way in which it 

 may be conceived nature worked. In another set of experiments I 

 have placed the flints, fixed and otherwise, at the bottom of a long 

 inclined trough, and have let the stones slide down and strike the 

 flint, or have put heavy weights behind them^ in a screw-jack action, 

 both directly upon the flint and with the interposition of a loose 

 pebble, but all with the same negative result. On the other hand, 

 when I have tried to make a clean chop off a mineral scores of times 

 I have been annoyed by a characteristic kick, giving rise to the 

 eraillure. I explain it to myself in this manner: — In an ordinary blow 

 one just brings the hammer upon the object, and is regardless of the 

 rebound, which generally initiates the return motion, and thus is 

 unrecognised ; but when one wants to hit in a certain place, in a 

 definite direction, there is an unconscious concentration of all muscular 

 power to make the blow fall at that particular spot, and even keep 

 the hammer there, and this voluntary muscular opposition off"ered to 

 the uprise of the striker forces it back, occasioning a secondary 

 but light blow. This can also be well seen and heard when one 

 attempts to drive a nail in an awkward place by a series of slow 



