642 



ISLAND OF ST. PAUL. 



[Ch. XXIX 



Hartung and I, when in Palrna, came to the conclusion that the waves 

 of the sea had never reached the Caldera, although they may have 

 penetrated for some distance into the Barranco de las Angustias, and 

 may have overflowed the space now overspread by certain strata of 

 conglomerate to the east of the Barranco. 



Since the cessation of volcanic action in the north of Palrna, the 

 most frequent eruptions appear to have taken place in a line running 

 north and south, from a to Fuencaliente, map, p. 628 ; one of the 

 volcanoes in this range, called Verigojo, g, being no less than 6565 

 English feet high. The lavas descending from several vents in this 

 chain reach the sea both on the east and west coast, and are many 

 of them nearly as naked and barren of vegetation as when they first 

 flowed. The tendency in volcanic vents to assume a linear arrange- 

 ment, as seen in the volcanoes of the Andes and Java on a grand 

 scale, is exemplified by the cones and craters of this small range in 

 Palma. It has been conjectured that such linearity in the direction 

 of superficial outbreaks is connected with deep fissures in the earth's 

 crust communicating with a subjacent focus of subterranean heat. 



By discussing at so much length the question whether the sea may 

 or may not have played an important part in enlarging the Caldera 



Tiff. 701. 



jSfine-pin 

 Kock. 



Entrance nearly dry 

 at low water. 



Map of the Island of St. Paul, in the Indian Ocean, lat. 8S° 44' S., long. 77° 37' E., 

 surveyed by Capt. Blackwood, E. 1ST., 1842. 



of Palma, I have been desirous at least to show how many facts and 

 observations are required to explain the structure and configuration 



