Rev. M. Frater — Volcanic Eruption, Ambrym Island. 497 



The volcanoes in the New Hebrides group work in sympathetic 

 agreement. Tanna volcano is the Stromboli of the Southern Seas. 

 The eruptions of this volcano are still heard as in the days of 

 Captain Cook. There is the "pillar of smoke" by day and the 

 "pillar of fire" by night. It is the great lighthouse of the South 

 Pacific. Like a revolving light it bursts out every three or four 

 minutes with great brilliance. A few years ago the regular 

 explosions suddenly ceased. The natives became alarmed ; they 

 had become accustomed to regard the volcano as the safety valve 

 of the district, and they had sufficient knowledge of mechanics to 

 understand that the closing of a safety valve is as dangerous in 

 a volcano as in a steam-engine. In company with a crowd of 

 natives, the resident missionary climbed to the edge of the crater 

 and discovered that the walls had collapsed and choked the " fire ". 

 But no sooner had Tanna closed down than the volcano on Ambrym, 

 300 miles northwards, became more active. The eruptions from 

 Ambrym, which had hitherto been spasmodic and irregular, now 

 took place at regular intervals, glowing at night with an intermittent 

 light resembling the flashing light of a lighthouse. Tanna remained 

 quiescent for a few weeks, and then, with a convulsive roar, the 

 imprisoned giant broke its bonds and awoke to life. The clock- 

 work regularity of the Ambrym volcano ceased and the eruptions 

 again became uncertain and spasmodic. 



The same sympathetic relations which exist between Ambrym 

 and Tanna also govern the workings of the Ambrym and Lopevi 

 volcanoes. Situated on neighbouring islands, only 25 miles apart, 

 their operations can be watched together. Violent activity in the 

 one is almost invariably answered by outbursts in the other. 



The destructive eruption of the Ambrym volcano with which 

 this paper deals occurred in December, 1913. Named Mount 

 Benbow, after one of the British warships which visited the group 

 in the early days of European settlement, the lofty cone of the 

 Ambrym volcano rises from the centre of an extensive ash plain, 

 over 2,000 feet above sea-level. In the neighbourhood of Mount 

 Benbow the ash plain is studded with a series of extinct craters, 

 occasional puffs of steam being the only indication of the pent-up 

 fire beneath. The ring-shaped crater wall which encloses the plain, 

 like a wall of circumvallation, first led the survey party of the 

 warship whose name the volcano bears to the now generally 

 accepted conclusion that the ash plain is the basal wreck of a 

 much loftier volcanic cone which was shattered by a volcanic 

 eruption, and that the island of Ambrym, with its volcanic soil, 

 now remains as a memorial to the destroyed volcano. For untold 

 centuries Mount Benbow had been at work puffing out steam which 

 at night reflected the glare of the molten lava bubbling within the 

 crater walls. So accustomed had the natives become to its presence 

 that the frequent outbursts occasioned no surprise. They cultivated 

 the soil up to the edge of the ash plain at the base of the volcano. 

 But all unknown to the natives, and to the French and English 

 residents who had their homes on Ambrym, there stretched from east 

 to west across the island a belt of volcanic fracture. On this fissure, 



DECADE VI. — VOL. IV. — NO. XI. 32 



