92 PREHISTORIC EUROPE. 



chert, "much more rudely formed, more massive, and less 

 symmetrical in form," than those ohtained from the cave-earth 

 and black band. They have been made, says Mr. Pengelly, "by 

 operating not on flakes, but directly on nodules, of which 

 portions of the original surface generally remain." (See Plate A, 

 Fig. 1, P- 11.) 



A study of the mechanically-formed accumulations on the 

 floor of Kent's Cave reveals the fact that between the time of 

 its earliest and latest known occupation by Palaeolithic man 

 and his congeners, considerable changes must have taken place 

 in the drainage-features of the neighbourhood. The breccia tells 

 us of a time when the cave was now and again occupied by bears, 

 and occasionally visited by savage men. During that period it 

 would appear that water, flowing from some of the adjacent 

 higher hills, ever and anon carried into the cave many fragments 

 of red grit — a rock which does not form any part of the hill into 

 which the cave opens ; but before the crystalline stalagmite began 

 to accrete, this process had altogether ceased — the drainage had 

 been diverted, and no mechanical sediment found its way into 

 the cave. Then, long subsequently, came a time of re-excavation, 

 when the crystalline stalagmite was undermined to some con- 

 siderable extent, and broken up — much, both of it and the 

 underlying breccia, being carried away. After this the cave was 

 again visited by predatory animals and by Palaeolithic man ; and 

 now and then flood-waters, bearing fine mud and silt, found 

 their way into the cave and spread their sediment over the floors 

 of chambers and galleries. Such inundations were intermittent, 

 and perhaps irregularly recurrent — long intervals of comparative 

 quiescence allowing the drip from the roof to commingle with 

 and calcify the floor-earth. During the slow accumulation of 

 this earth, hysenas seem to have occupied the cave for long 

 periods, and it was certainly also the haunt of other predatory 

 animals, such as lions, bears, and the extinct tiger-like machair- 

 odus. Man was likewise at intervals a visitor, and possibly a 

 resident while the cave-earth was forming. At all events he 

 certainly was so during the accumulation of the black band — for 



