°-9l» Transactions. 



o 



ing to within half a mile at the sea. The hills around ranged fromT500 ft. to 

 1,245 ft., and we considered everything inside this barrier as being quite safe. 



Just about the time, or shortly before, the last stream reacheclTthe sea 

 we saw a dense volume of black smoke rising from the hilltop on the east 

 side, near the entrance to the valley and overlooking the hospital. When 

 day broke we discovered the top of the hill was being blown out, but as 

 yet there was no appearance of fire ; only some continuous expulsive force 

 was driving the hilltop out. There were no separate explosions observable. 

 The force was continuous. Soon, however, fire appeared, and the force in- 

 creased quickly, so that one could observe the hill steadily diminishing in 

 height. The side of the hill looking west was acted upon, and decreased more 

 quickly than the other sides, and about 10 a.m. on the 7th lava began to flow 

 down the hillside into the valley and through part of the hospital compound. 



(e.) The ground in the valley could be felt in motion — a kind of heave 

 —not violently, but reminding one of a slight motion at sea. This motion 

 was not continuous, but at very short intervals. 



Shortly after 10 a.m. an explosive eruption blew the hospital and other 

 buildings into the air. The force of this explosion was terrific. First a 

 great sheet of what appeared to be electric flame flashed from the ground, 

 and immediately following was a mighty roar and crash like myriad 

 thunder-claps one piled on another. The heat, too, was intense. We could 

 see for an instant only the corrugated iron spreading out like scintillating 

 glass, and then it was- gone. Explosion then followed explosion almost 

 continuously for four days at least. Sometimes there would be a short 

 interval, but the intervals did not last long. 



(/.) We discovered at daylight that another lava-stream had flowed 

 behind our hills towards Craig's Cove. This stream stopped on the plain 

 about 500 yards from the beach. This stream was the biggest of all, being 

 in some parts about three-quarters of a mile wide. 



(g.) About 3 p.m. on the 7th a submarine volcano broke out about a 

 mile from the shore off Lamb Point. Soon an island was formed, and within 

 sixteen hours had joined the mainland. After four days the activity of this 

 volcano ceased. 



On Tuesday, the 9th December, a geyser suddenly broke out a few hundred 

 yards inland from Craig Point. Water must have been forced to a consider- 

 able height, for we were drenched in a mud bath while over 500 yards from 

 the shore. The geyser lasted for probably fifteen minutes or more. Im- 

 mediately after the geyser ceased a roar like a rushing torrent was heard. 

 Very soon a river extending in width from the trading-station at Craig 

 Point to Malver tore its mad rush to the sea. For half an hour or so there 

 was a great volume of water, which gradually diminished in volume, and 

 apparently in speed. This river ran for at least six hours. 



On Sunday, the 7th December, there were six distinct craters in the 

 vicinity of Dip Point, West Ambrym. The whole district was undoubtedly 

 a fairly recent volcanic area. In the valley behind the hospital, as well as 

 at Craig's Cove, outcrops of lava could be seen at various points, and there 

 was little evidence of weathering, the lava in man}' places appearing 

 rugged, as it does soon after cooling. 



Petrography. 



The rocks oi Ambrym do not appear to have been described hitherto, 

 and it has therefore been thought advisable to add to this account of the 

 eruption by Dr. Bowie a few notes on the rock-specimens that have been 



