Lieut. Nelson on the Geology of the Bermudas. 123 



can scarcely imagine the probable depth to which such accumulations are 

 likely to be consolidated. As a tolerably general rule, the upper strata are 

 less compact throughout the Islands than the lower ones ; but there is a con- 

 tradiction to this, not only in the large and deep sound cliff from which our 

 works at Ireland are supplied, where the bottom is as soft as the top, but in 

 the still more remarkable instances afforded by the beds of sand, mentioned at 

 pages 106 and 107, as lying just above high water along much of the south 

 sides of St. George's, and of the Main island. These sand beds lie under 

 cliffs of good rock, sometimes fifty feet high. Why has not the rain water 

 deposited the lime which it cannot but have dissolved in its passage amongst 

 these beds ? 



I had a tube, two inches square inside, and six feet long, filled with sand, 

 suspended vertically from a shelf. For two years water was kept dripping on 

 the upper end, with no greater interruptions than those which might have 

 occurred from an occasional want of rain ; but on opening the tube at 

 the end of that period there was not the slightest appearance of cohesion 

 amongst the particles of sand. Want of opportunity for the water to eva- 

 porate through the sides might account for this ; but such heavy exceptions to 

 an extensively applied general rule, like that regulating the consolidation of 

 the Bermuda rock, are very embarrassing. 



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