1 882. 5 Trans. N. V. Ac. Sci. 



been underground water-courses, when the land stood at a different 

 level ; and the very form and arrangement of the cave, just now alluded 

 to, in the chalk, near the Giant's Causeway, as being of artificial origin, 

 showed that it was nothing but an ordinary limestone cave, which had 

 been laid open by the encroachment of the ocean, and subsequently 

 modified by atmospheric and aqueous agencies. 



The argument, that the three caves described, on Staffa, were placed 

 by design directly opposite lona, would have more force if there were 

 not other caves on the island not so situated ; nor could great stress 

 be laid on the approximate similarity of the measurements in case of 

 two of the caves. 



In conclusion, it seemed futile to argue that the action of the sea 

 and of running water and of the atmosphere, as we find them at Staffa 

 now, were unable to have excavated these caves in times past. Much 

 less was it safe to drag in chalk caves as evidence of the artificial 

 character of caves in basalt. The only argument of any weight in 

 support of the whole theory seemed to be the general statement that 

 caves such as these are not ordinarily met with in rocks at all resemb- 

 ling in character those of Staffa. 



Mr. KUNZ enquired as to the depth of water and form of the ter- 

 minal slopes in the caves. 



Mr. Whitehouse replied that there were no appearances of change 

 of level at Staffa, and that the force of the waves did not reach the 

 upper part of the caves. The depth of water in the Clamshell Cave 

 ^was nine feet at the inner end, and the cave there terminated in an ir- 

 regular steep slope. In recapitulation of the principal arguments : 



1. There is no probability that five caves in a thousand yards would 

 be formed by five different causes. 



2. If a trap dyke formed Fingal's cave, it is geologically impossible 

 that there was any " fault" in Boat, Cormorant's or Clam Shell. 



3. There is no "fissure" above Cormorant's cave. The triangular 

 opening in its columnar basalt corresponds to that in the confused 

 basalt above Fingal's. 



4. Confused basalt could not crack in a long straight fissure. 



5. Tuff, underlying columnar basalt, makes a rocky shore sur- 

 mounted by a steep slope of basalt. The basalt is practically solid — 

 iorms a " pier" not a " hay." 



6. Why was the debris removed to an unknown distance .-* 



7. Why did the momentum of the waves limit itself without appa- 

 rent cause, and leave thin walls of tuff or basalt } 



The President stated the impossibility of deciding such a question 

 without a visit to the locality. He had seen many coasts undergoing 

 erosion, but never any excavated like this, merely by the force of the 



