GODDTG PETROLEUM. 
39 
geological divisions are called tlie Coralline and tlie Scot- 
land formations. 
The Coralline formation , occupying by far the greater por- 
tion of the superficial area of the island, rises from the sea- 
coast in several and successive lines of terraces, which as 
seen from the Westward, very generally present mural or 
precipitous faces to the observer. These heights and the 
intervening lands are here and there intersected by deep 
ravines or gullies, and the table lands, either flat or gently 
undulating, which crown the terraces, not unfrequently 
show considerable hollows or depressions, favoring the sup- 
position of the action of currents and eddies of the ocean, 
while the land lay submerged at various periods under its 
waters. The rocks composing the coralline formation are 
essentially limestone and consist of a vast accumulation of 
whitish calcareous matter gradually formed, however modi- 
fied in character and density they may have been, while 
subjected to the alternations of upheaval and submergence 
they have undergone during periods prior to the present 
elevation of the land. The calcareous mass varies much in 
thickness ; and as ascertained by the heights of the deeper 
ravines, and the depths of the many wells sunk in various 
parts of the country for the supply of water, it must in many 
places exceed two, or even three hundred feet. In other 
localities the thickness diminishes to a thin layer merely 
and gives place to the outcropping of some of the Scotland 
series of stratified rocks, upon which the great bulk of the 
coral limestone rests. The material of this formation is 
chiefly made up of hard and compact limestone consolidated 
probably by pressure — beds of conglomerate formed of the 
exuviae and the fabrics of the coral animals — beds of sand 
and of marls — calcareous sandstone ( dripstone J an excel- 
lent material for building purposes. Marine shells every- 
