JONES GEOLOGICAL FEATURES OF THE BERMUDAS. 25 



around the vegetable matter, first takes place, and when the decay 

 becomes perfect the vacuum is filled by the same material. 



Another circumstance I will noAv relate, which tends in some 

 measure to shew the similarity of the Bermuda phenomena to those 

 of the Pacific. Below the Paget Sand Hills, and on the shelving- 

 beach between high and low water mark, stand some remarkable 

 rocks of the same consistency as the shore rock. One in particular 

 stands perfectly isolated from the rest, and by the action of the 

 waves has its base worn away, making it look like a large head upon 

 a short neck. Although these rocks present a curious appearance, I 

 should not have paid particular attention to them had I not found the 

 occurrence of similar shaped rocks recorded in Dana's work, as exist- 

 ing at Waterland, one of the Rawehe Islands, in the Pacific. The rocks 

 instanced by Dana, however, differ somewhat in consistency, being 

 almost wholly composed of large fragments of corals of the genera 

 Astrcea and Madrepora, and imbedded shells, whereas the Bermuda 

 examples vi'cre composed of the usual comminuted shell and coral, 

 with imbedded shells. They nevertheless assimilate in many par- 

 ticulars, and aflbrd evidence of similar agencies at work in coral 

 groups, in the northern as well as the southern hemisphere. 



From soundings taken along the outer reefs, it has been found 

 that the Bermudas rest upon a partially columnar structure, for 

 immediately outside these outer reefs the descent is precipitous, 

 more especially on the southern side. To the westward, however, 

 the column appears to be continuous for a space of thirty miles, for 

 in that distance occur three or four masses of rock at a depth of 

 about thii'ty fathoms. These are well known to the fishermen, who 

 reap rich harvests when they visit them, fish appearing always to 

 congregate in greater numbers wherever rocks lie. 



It may be well to notice, that this extension of the Bermuda 

 column is directly towards that point of the main land of America, 

 which juts out for a considerable distance eastwardly towards the 

 Bermuda extension, viz., Cape Hatteras. I mention this in order 

 to point out a probability that in ages past the Bermuda column 

 may have heen attached to the main ; for although I conceive, 

 without conclusive evidence to the contrary, that the Bermuda 

 column owes its origin to volcanic action, yet still as it at present 

 remains a mystery, it will be well to consider the question of origin 



