CORAL LIMESTONE. 7 



any where continuous for more than a yard or two, 

 we had a succession of wading and scrambling that 

 was rather laborious. Arrived at the island, the 

 first thing that took my attention was a large deve- 

 lopement of hard brown rock, like that on Bunker's 

 Island. Both the island and the reef were elon- 

 gated in an east and west direction, the island being 

 half a mile long and not more than 300 yards broad. 

 It consisted in the interior of piles of loose sand, 

 covered by a dense wood of pretty large trees, with 

 broadish leaves, most of which had a white brittle 

 wood, and grew in a singularly slanting position, 

 the stems frequently curving at an angle of 45°, 

 although three or four feet in circumference. The 

 beach of the island was steep, about twenty feet 

 high at low water, and composed partly of sand and 

 partly of stone. The sand was very coarse, com- 

 posed wholly of large grains and small angular 

 pieces of broken and comminuted corals and shells, 

 with some larger worn fragments of both intermixed. 

 The stone was of precisely the same materials, but 

 very hard, and dark brown externally, although still 

 white inside. It sometimes required two or three 

 sharp blows with the hammer to break even a corner 

 of it off. Its surface was every where rough, honey- 

 combed, and uneven ; the beds were from one to 

 two feet in thickness, with occasionally in the fine- 

 grained parts a tendency to split into slabs or flags. 

 It was perfectly jointed by rather zig-zag points 

 crossing each other at right angles, and splitting the 



