ON THE GEOLOGY OF THE NORTH-EASTERN WEST-INDIA ISLANDS. 



19 



The island of Saba seen from S:t Enstatiii 



Saba seen from S:t Bartholomew. 



-■■•-I M7*ac7i/ul%> 



Hövan oP 

 got torn 



SvlpkicrDeposit 



S:t Eustatius, also a Dutch possession, is a small, entirely volcanic, island, 6,7 kilo- 

 meters in length and 4,7 kil. in breadth. In the southern part is a conical volcanic moun- 

 tain called »the Quill» or the Punch Bowl. The summit is one of the most regular cra- 

 ters. The mountain reaches about 594 meters above the sea-level, and the opening of the 

 crater is about 740 meters in diameter. The whole crater is overgrown with a rich tro- 

 pical vegetation. The slope of the mountain is very steep, in the higher parts about 45°, 

 but on an average about 25°. The exteriör surface of the volcano is grooved by radia- 

 ting furrows hollowed by rain-water. The volcano, of which no eruption is recorded, seems 

 never to have emitted lava-currents, the whole cone being constructed of loose materials, 

 boulders and trachytic tufa. In the lower parts surrounding the mountain the tufas is dis- 

 posed in very regular strata. On the western slope is a small hill called Round Hill, which 

 seems to be a parasitical cone. 



According to Maclure*) there is on the south-east slope of the cone a lime-deposit 

 of corals and shells, »similar to those found in the sea». He gives the following descrip- 

 tion: »The whole of this marine deposition dips to the southwest at an angle of upwards 

 of 45 degrees from the horizon, resting upon a bed of cinders, full of pumice and other 

 volcanic rocks, and is immediately covered by a bed of madrepore, sand and cinders mixed 

 together, with blocks of volcanic rocks so disseminated that there can be no doubt of the 

 volcanic origin of the substance above and below the madrepore rock, which may be from 

 five to six hundred yards thick». I have not visited the spöt, but to judge from the de- 



*) Journal of the Acad. of Nat. Se. of Philadelphia, Vol. I Part I p. 147. 



