Lieut. Nelson on the Geologi/ of the Bermudas. 109 



Salt Marsh A* is on a level with B : as far as I can judge, all the others in the 

 islands are not above the sea level. The water is almost fresh, but in sum- 

 mer, these ponds become stagnant and very offensive. 



Encroachments. 



Land on Sea. — The harbours and inlets of Bermuda share the same fate 

 as those of all other places, where it is easier for the sea to introduce silt and 

 sand in its first strength, than to withdraw it when the velocity of its waters is 

 reduced by the obstructions of the sand-banks, rocks and reefs forming the 

 confined and labyrinthine passages among coral groups. 



Thus at the head of Crow-lane, Bermuda or Main Island, within the memory of the present 

 generation, ships of some burthen used to lie at wharfs, where now scarcely a large boat can repair 

 at all tides. The same has occurred in the narrow channel between Ordnance Island and the 

 Market-wharf at St. George's, but to a far greater extent. 



The Flatts Inlet, entrance to Harrington Sound, is perceptibly filling, notwithstanding the 

 benefit it receives from the Sound as a backwater. ^ 



Sea on Land. — There is a limit to these encroachments ; for although the 

 action of the sea is powerful enough to undermine the ordinary strata, yet 

 when it reaches the hard calcareous rock it can proceed no further; and this 

 stone, which I shall hereafter designate as '^ Base rock,' will be found wanting 

 under all the recent landslips ; hence, with these exceptions, I know but one 

 instance of marine encroachments. In 1801 Shelly Bay scarcely existed : what 

 is now the mouth, was at that time a row of sand hills ; and the road on the 

 north side lay close within. Some free blacks who lived there, being in want 

 of fuel, cut down the plants which kept these sand hills in a solid state. Being- 

 no longer duly opposed, the sea quickly broke through, and now retains pos- 

 session of the ground at least 100 yards in rear of the old road, traces of 

 which are still visible. The Mangrove Swamp between the beach and the 

 present road, was until then a garden. 



Sand Encroachments. — Though there are objections to the last being- 

 termed a strictly geological fact, yet I have introduced it, and the following 

 details of the sand flood at Elbow Bay, on account of their great utility. 



The proprietor of the principal part of the land of this bay, the venerable Captain Lightbourne, 

 remembers an attempt about seventy years ago, when the inhabitants expected an attack from the 

 French and Spaniards, to form a breastwork along the sand-hills, which then, as at Shelly Bay, 

 skirted the coast. In doing so, they cut through the natural protections given by the sea-shrubs 

 and creepers which usually abound in such places. From that day the sand, supported by con- 

 stant supplies from the sea, has steadily proceeded up the hill to the very summit, a height of 

 about 180 feet. It is, however, surprising to observe the singular state of arrest under which the 



* Map, PI. VI., Fig. 2. 



