﻿Vol. 66.'] VOLCANO OF MATAVANT7 IN S AVAIL 635 



At Matautu, 2 miles west of the lava, the damage was due to the 

 Ua Sami formed by the action of the lava on the sea-water, 

 which was considered even more poisonous than that discharged 

 from the crater. Many cocoa-nut palms had been damaged and 

 some had died, but most had recovered ; while several breadfruit 

 trees were killed entirely, and some recovered only with the loss of 

 their upper branches. 1 



During the night of my visit to the crater some large frigate- 

 birds of two kinds, black and white, with long tails, were con- 

 stantly circling about the crater at a height of several hundred 

 feet, and were clearly visible in the lurid reflected light. They 

 have been noticed by others to whom I have spoken. 



Mr. H. I. Jensen (op. cit. pp, 666-70) gives a full account of the 

 petrology of the Samoan lavas : I quote only his conclusions. Petro- 

 logically the Samoan rocks are very like one another and the basalt 

 near Auckland (New Zealand). The olivine content varies from nil 

 to nearly 50 per cent. Most of the rocks are hypohy aline, if ob- 

 tained from a depth beneath the surface of a now ; hyaline or 

 hemicrystalline, highly vesicular or scoriaceous, when obtained 

 near the surface. The earlier rocks erupted were probably augite- 

 andesites, the later rocks being olivine-basalts. The new now is 

 richer in iron-ores than any of the old flows. Mr. Jensen does not 

 discuss the reason of the high temperature and great fluidity of 

 the lava at the moment of the eruption. 



Comparison with Kilauea. 



It may be well to discuss the many resemblances and few 

 differences between the volcanoes of Matavanu and Kilauea in 

 Hawaii, which latter I visited soon after the former. Both are of 

 the effusive type, that is, characterized by the discharge of lava 

 very slightly charged with steam and other volcanic gases, and 

 hence little subject to explosive action : in which respect they 

 contrast strongly with the volcanoes of the West Indies and 

 Central America, where most of the recent eruptions have been 

 highly explosive, and attended with the discharge of a vast 

 quantity of ashes, lapilli, and pumice, but little or no lava. Not 

 that explosions have been entirely absent in these Pacific volcanoes : 

 I found in the walls of the crater of Matavanu some beds of tuff, 

 that is, consolidated ash, but they were subordinate in thickness 

 -and importance to those of lava ; and also on the flanks of the cone 

 some bombs of basalt. Similarly on Kilauea I saw a bed of lapilli 

 about a foot thick, but it was on the slopes of the old encircling 

 cone comparable to Monte Somraa, and there was no trace of such 

 about the working crater. Moreover, its amount was strikingly 

 different from the deposits of ash ranging up to 100 or 200 feet in 

 thickness formed in 1902 on the Soufriere in St. Vincent, or on 

 Montagne Pelee in Martinique, or on Santa Maria in Guatemala, or 

 even those formed on Vesuvius in 1906. 



1 No human lives were lost by the eruption. 

 Q. J. G. S. No. 264. 2 x 



