ON RAINS CAVE, LONGCLIFFE, DERBYSHIRE. 249 



Other hand, the former bed was undoubtedly introduced as a 

 mixture of earth and stones, sometimes the one preponderating, 

 sometimes the other ; and its frequently weathered stones 

 indicated that it consisted largely of external sub-soil. In a talus, 

 the larger materials tend to spread out, being more given to rolling 

 than the finer, which, on the other hand, are rapidly lost in the 

 interstices, before the fringe is reached. As the cave entrance 

 when the breccia was introduced was almost certainly more 

 forward than at present, the zone of fine detritus would also be 

 more forward, the breccia being its fringe. This, however, 

 scarcely explains the greater angularity of its fragments. A fall of 

 rock at a cave mouth does not necessarily involve a fall of sub-soil 

 as well ; in the implied contingency it is reasonable to think that the 

 rock-slip would resolve itself into a coarse angular debris, with 

 comparatively little finer material. The overlying loamy seam, 

 which was identical with the intersticial loam, had all the 

 appearance of rain-wash. In being washed down the cave, it 

 would naturally sink into the interstices of the shingle before 

 accumulating above it, or invading those portions beyond. This 

 is just what was found to be the case. The loam formed a 

 distinct bed only where the breccia was intersticially filled below ; 

 while nearer the back of the cave, where this deposit was more or 

 less open, the loam occurred only in obscure patches. The lack of 

 bones and other foreign objects in these lower beds was probably 

 due to the cave being sealed up during the time of their 

 accumulation. 



The sequence of the deposits suggests the question of time. 

 Time, as measured by years, plays but a small part in the history 

 of most cave deposits, and it is so in that of the present one. 

 The wheel-made potsherds carry us back at most to the Roman 

 occupation, say, 1,700 years ago; and the iron objects ttiay be a 

 few centuries older. These are the extreme limits : it does not 

 follow that these objects are so old. We know that previous to 

 the introduction of iron into Western Europe there was a stage of 

 time characterised by certain traits of civilisation and art, known 

 as the Bronze Age, because that alloy was the best available 



