1865.] Science in the Provinces. 531 



the sea. It would appear that the water entered through each of the 

 four external openings, and after flowing almost horizontally, was dis- 

 charged through a highly-inclined shaft within the cavern, the walls 

 of which shaft are polished and scratched as if by the long-continued 

 action of running water charged with detritus. It was also evident 

 that the introduction of material was intermittent, the volume of the 

 stream having been at times so small as to leave parts of the galleries 

 comparatively dry, and so allowing the formation of a cake of stalag- 

 mite. Such engulphed streams exist in some caverns at the present 

 day. 



The two remaining methods of introduction which are mentioned 

 by the author as probable, are the introduction of accumulations by 

 the sea, and that by occasional land floods ; but the instances which 

 seem to support these latter hypotheses are as yet somewhat isolated. 



