Art. IX. — TliG Active Volcano on Tana, Neiv Hebrides, with 

 some remarks on. tJte Cause of Volcanic Action. 



With Map and Plates 5, 6, 7 and 8. 



By Frederick A. Campbell, C.E. (Melb.) 



[Read 11th October, 1888.] 



Tana is one of the southern islands of the New Hebrides 

 group, and lies approxiniatel}^ in 20"" south latitude and 

 170° east longitude. It is about 30 miles long by 12 miles 

 wide, and is densely covered with the most luxuriant 

 tropical vegetation. The interior is occupied by a range of 

 mountains which rises to a height of about 2500 feet, and so 

 far as I know, has never yet been explored. The shores are 

 partly fringed by a narrow coral reef, outside of which the 

 water deepens rapidly, and good anchorage is difficult to 

 find. There is only, or more correctly speaking was only 

 until recently, '^ne harbour on the island, viz., Port Resolution, 

 a picturesque basin about one mile in diameter, situated 

 upon the south-eastern side and opening towards the north. 



Four-and-a-half miles to the north-west of this harbour, 

 the active volcano Mount Yasur, is situated. It rises from a 

 plain or wide flat valley which sej)ar;ites the elevated land of 

 the Port Resolution district from the still moi-e lofty ranges 

 of the interior. A ridge 100 or oOO feet high extends from 

 the harbour towards the volcanic cone, descending as it 

 jipproaches that hill, the summit of which stands about 500 

 feet above the plain beyon<l and 70!) feet above the sea level. 



The volcanic district, that is the area over which ai'e 

 .scattered traces of volcanic action, past and present, is about 

 20 square miles in extent, being a belt abinit 2| miles 

 wide, extending from the sea coast outside and to the south 

 of Port Resolution, for a distance of seven miles to the active 

 cone of Mount Yasur. 



Plate 5 gives a vertical section di-awn through this part 

 of the island. Plate 6 gives a plan of this district upon 

 which I have marked the approximate position of the various 

 volcanic phenomena. 



Commencing at the mo^t southerly, these may be biiefly 

 catalogued as follows : — 



Hot springs on the outer sea coast. 



