118 



Lieut. Nelson on the Geology of the Bermudas. 



highest pinnacle bears the ultimatum of the desired evidence of ' Diluvial Agency,' a stratified 

 summit, as pointed out to me by the keener eye of my late brother officer, Lieut. Browne, R.E. 



This monument to departed strata, stands in a Serpuline reef, which is as usual tabular, and 

 appears above low water. The largest rock is about sixteen feet high ; and like all those which 

 have withstood the onset of the Atlantic, is composed of " base rock." 



Internal Evidence. — Ireland is the only place, as far as I am aware of, which has supplied such 

 arguments ; the deposits of red earth in fig. 5, contain stones that would have been too heavy 

 for the wind to have moved without utterly dispersing every grain of the soil containing them. 

 From the number of these deposits, we are warranted to conclude, that five or six such cata- 

 strophes have befallen these islands; though the organics establish clearly enough, that as delicate 

 land shells, they and the strata in which they are imbedded could never have been produced 

 under water ; and if a rock in the heart of an island, and at its lowest point, presents animal 

 remains possessing even colour and membranous tissue, with a considerable degree of perfection ; 

 the superincumbent masses cannot boast of any great claims to antiquity ; hence the expression 

 ' Diluvial Agency,' as the heading of this section must not be restricted to the Noachian deluge, 

 but to the repetition of several probably subsequent, local ones, and the results of distant vol- 

 canic action. 



Caverns and Pinnacles. 

 The caverns are numerous, and many of them very beautiful. The largest, 

 and, geologically speaking, the most instructive, is Basset's, near Somerset- 

 bridge. It is said to extend for more than a mile ; but the first few hundred 

 yards of toilsome progress usually satisfies the curiosity of the majority of 

 its visitors. It seems to be comparatively recent, from the fresh state of 

 its surfaces, and the small quantity of stalactite observable; this absence 

 of incrustation, however, renders the origin of this cavern very palpable; 

 namely, the undermining of the substrata by the sea, the waters of which 

 lie in pools at the bottom. Hence we may consider such caverns as hollows 

 produced by internal landslips; from the most normal of which, to the 

 simplest niche, there is every intermediate point of transition. The north 

 side of the Main island is to a remarkable degree indented with these re- 

 cesses ; and when they occur in more sheltered places, are sure to be rich 

 fields for the naturalist. 



Fig. 14. 



