110 Lieut. Nelson on the Geology of the Bermudas. 



invader stands before the children of the soil. A few straggling cedars,widely scattered in advance 

 of the wood which now bounds the space, have been passed by this sand flood, yet the dazzling, 

 dry, and almost snow-white sand is checked, before the front rank of the trees, in a steep bank, 

 varying from ten to twenty-five feet in height, and so remarkably well defined that scarcely a 

 particle is scattered beyond a distance of twenty yards. As soon as the mass shall have over- 

 topped the woods, I know nothing capable of opposing its progress, as there are no streams at 

 Bermuda to act like the little brook in St. Owen's valley at Jersey*, which has so effectually 

 stopped the march of the Quenodis. 



Although this inroad commenced so long ago, yet the principal advance has been since 1807, 

 from which date about 200 yards have been gained on the eastern side. Before I left the colony 

 in March 1833, the sand had reached the northern corner of a cottage belonging to a man called 

 Ned Keel (on Mr. Butterfield's estate); and the top of the bank, eight feet high, was on a level 

 with the eaves of the shed. During the last fourteen years it has progressed, at this point, only 

 about forty yards, in a bed from four to eight feet deep, in consequence of the repulsive action 

 of a thin beltof cedars just below. Very near this spot also, is a small circular group of the same 

 trees, which the sand has passed, and imbedded to the depth of from six to eight feet ; but the 

 space within has been so perfectly screened, that the bottom of this little oasis is the natural green- 

 sward. 



There is another encroachment at Tucker's Town, said to have taken place about sixty years 

 ago ; and has crossed the neck between Harrington's Sound and the sea ; but beyond this it does 

 not seem inclined to move. The sand has not been stopped, at the eastern extremity of this 

 beach, where the bluffs commence, by their very considerable declivity, — though it has been most 

 effectually at the crest of the slope, by a natural fence of sage bush, growing partly in the soil 

 and partly in the sand ; which, as it ascended, seems to have thus rolled on with the seeds of de- 

 struction to its progress, in its own bosom. 



The same operations appear to have occurred throughout the sand tracts at and near Great 

 Turtle Bay. Whatever scheme may hereafter be executed for the further defence of the south 

 side, it will be well to remember the fate of Captain Lightbourne's property ; so that if a military 

 road be formed over such ground, to make it on the turf, and on no account to cut through it. 



Hence also, where a stream of water cannot be commanded, plantations of trees, suitable to the 

 soil, will for a long time maintain a very efficient opposition ; and though it is to be feared, that 

 eventually they must succumb, where turf and creepers have not established themselves, still, 

 to have effected the preservation of a district for a generation or two, cannot be considered as 

 the attainment of a trifling object. 



In Elbow Bay the sand contains, generally on or near the surface, layers, 

 scales, and tubes of calcareous stone, which cannot have been many years in 

 forming, though 1 have not sufficient data to determine the precise number. 



The greatest thickness of the layers is about 11 inches ; and although found on the surface, they 

 are not, I apprehend, produced there, but at a few feet or inches beneath. The sand on the 

 weather side of the little saddles is constantly blowing away, and the edges of the reverse strata, 

 or rather lamina, becoming exposed and undermined, fall down. 



An inspection of some of these slabs will prove how perfectly, recent specimens may be con- 



* See a paper of mine, published in the late Quarterly Journal of Science for October 1829, on 

 the Geology of Jersey, and its relation to that of the Devonshire and Norman coasts. 



