856 Matavanu : A New Volcano in Savaii. [April 29, 



WEEKLY EVENING MEETING, 



Friday, April 29, 1910. 



His Grace the Duke of Northumberland, K.G. P.O. D.C.L. 

 F.R.S., President, in the Chair. 



Tempest Anderson, Esq. M.D. D.Sc. M.R.I. 



Matavanu: A New Volcano in Savaii {German Samoa). 



Though not the seat of government, Savaii is the largest of the 

 Samoan Islands in the Central Pacific Ocean. It has a backbone of 

 volcanic mountains, some of ^Yhich rise to a height of over 4000 feet ; 

 most of them are extinct or dormant, but there have been several 

 small eruptions within the last 200 years, and one as lately as 1902. 



The Volcano of Matavanu was formed in 11)05 to the north of 

 the main ridge, and near the centre of the island. The early part 

 of the eruption was characterised by explosions, and the ejecta were 

 mainly solid, but later on an enormous quantity of very fluid basic 

 lava has been discharged. This has flowed by a sinuous course of 

 about 1 miles into the sea, devastated some of the most fertile land 

 in the Island, and covered it up with lava fields probably not less 

 than twenty square miles in area. 



The crater contains a lake, or rather river, of molten lava so 

 fluid that it rises in incandescent fountains, beats in waves on the 

 walls, and rushes with great velocity down into a gulf or tunnel at 

 one end of the crater. The lava, still liquid, runs in a passage, or 

 perhaps system of passages, under the surface of the lava field, its 

 course being traceable by a line of large fumaroles till, still in a fluid 

 condition, it reaches the sea, into which it flows with energetic 

 explosions and the discharge of large volumes of steam, black sand, 

 and fragments of lava. Where the action is less violent a struc- 

 ture resembling that of some varieties of pillow lava is produced. 



Photographs were shown on the screen illustrating the crater, 

 the lava fields, with their subsidences and tunnels, the explosions, 

 as well as others which enabled a comparison to be made between 

 the devastated and untouched parts of the Island. 



[T. A.] 



