238 AN ANCIENT PORTLAND INTERMENT. 



the island, and were doubtless introduced into the fissure during 

 the process of filling up. The valve of the little marine Corbula 

 gibba was probably carried up from the shore by a sea-fowl to 

 whose foot it was attached ; it is improbable that so small and 

 unattractive a shell could have been deposited with the remains 

 intentionally. The last point for our consideration is the character 

 of the deposit. Is it an interment, and, if so, is it in its original 

 state, or has it fallen in from above through some disturbance, 

 causing its support to give way, and hurling its contents into the 

 fissure 1 I am inclined to take this view for the following reasons. 

 It has been seen from what has been already said that the 

 fissures of the island pass through the whole series of the Portland- 

 beds down to the Portland clay. The amount of pressure 

 of rock ninety feet in thickness upon a foundation of clay must 

 produce a disturbance affecting the superincumbent beds, causing 

 settlements, cracks, and fissures. Unlike seismic action, which 

 distorts, dislocates, and subverts whatever opposes it, the effect by 

 pressure upon rocks resting upon an unstable base of clay or sand 

 often results in a subsidence, causing dislocation at the weak points, 

 and the initiation of a fissure. Accepting this view I consider that 

 the interment was originally near the surface, over an incipient 

 fissure, or fell in by an accidental local disturbance. Owing to the 

 absence of a large proportion of the human and animal-remains in 

 the fissure, I think it probable that these slipped over the Whitbed 

 ledge and passed on into the cavity below, which was limited in 

 space, being only three feet wide, and insufficient for the interment 

 of four bodies and for the friends who assisted at the obsequies. 

 The layer of stalagmite must have been deposited on the walls of 

 the fissure, and removed from its original position during the 

 process of filling up. 



