CAUSE FOR THE ORIGIN OP THE TRADITION OP THE FLOOD. 2G7 



The two most usual explanations that have been proposed 

 to account for the Head are, 1st, that the rubble was cbiven 

 over the old cliffs at a time of excessive rainfall during the late 

 Quaternary or Glacial period ; 2nd, that during the Glacial 

 period, sheets of frozen snow or ice shd down the hill slopes 

 above, and carried with them the debris of the surface. 'I'he 

 objection to the first is that the rain draining off the land 

 would have worn water-channels, and the debris would 

 have been spread out in the form of cones of dejection and 

 would also liave been waterworn; whereas there are no 

 special water-channels, and the debris is spread over the cliff 

 edge in the form of broad sheets conterminous with the 

 extent of the cliff itself. Nor, as a rule, are the rock or 

 bone fragments in any degree worn. For these and other 

 reasons given in the paper read before the Geological 

 Society,* this cause must be considered inadequate. 



The agency of Snow and Ice is open to fewer objections. 

 It would in fact account for many of the phenomena. 

 Where the slopes were sufficient, frozen masses of snow or 

 sludge might carry down with them the surface di^hris a^nd 

 lodge it at the foot of the cliflTor slope, but the angles of the 

 slopes above, and the extent of the gathering grounds, are in 

 most cases insufficient, and no instances are recorded where 

 such debris, formed at the present day, contains perfect land 

 shells and sharply fractured bones. The grinding of the 

 mass, as it slid down, would be fatal to the preservation of 

 fragile shells, and to the retention of the sharp angles of the 

 bones. A still more serious objection to either of these 

 causes is the distance to which the debris has been projected 

 and the large blocks moved, of both of which we shall give 

 instances presently. It must be borne in mind also that it is 

 very unlikely that a surface subject to the frequent occurrence 

 of these slides could contain organic remains of the character 

 found in the Head. As often happens, explanations are 

 tendered in consequence of their satisfying some of the 

 conditions of the problem, but without satisfying others, or 

 having regard to the consequences Avhich must ensue were 

 the assumption adopted. 



Ossiferous Fissures. — Another feature connected with one 

 phase of the Rubble-drift is that relating to the fissures, often 



* Quart. Joxirn. for 1892, p. 326. 



