320 ' Scientific Intelligence. 
rock is formed of Conch and other shells, together with coral frag- 
which, being consolidated in various degrees, are converted into 
rock of different qualities. * * * * TI 
ance, but softer and more porous. When first exposed it is quite 
white, and is inconveniently bright and dazzling under a tropical 
sun; but it becomes of a dark ashen-gray color alon 
and more or less so elsewhere, when exposed to the weather. Its 
the south-west of New P 
the rock is hard and homogeneous, and may be raised in good 
blocks for building purposes. The looser and softer kinds of rock 
are found usually on the hill tops. A variety offering a singular 
counterfeit of true odlitic structure is found at or near White Gay, 
xuma, and elsewhere; but the spherules are solid, and have bees 
ung chalk formation. 
The “red earth” previously mentioned as forming, generally 
speaking, he B is at times interstratr 
fied with the rock, and sometimes it is incorporated with it. It 18 
complete clue to the characters of this substance. Some of the 
varieties from the Del: i 
2 
the varieties gave off ammonia, whether retaining organi¢ texture — 
