GEOLOGICAL OBSERVATIONS 



Messrs. Priestley, Murray and Mackay. It illuminated 

 the whole steam colunm to the base of the musliroom. 

 We observed that the top of this column then spread 

 out gradually, first into a club-headed lump, then into a 

 mushroom-like form. 



At 3.25 P.M. a remarkably bright glow suddenly ht up 

 all the lower part of the steam column above the crater. 

 This was seen by Shackle ton, Priestley and Day. 



By 3.45 P.M. the steam cloud had spread out much 

 more and had besides risen higher, and the first formed 

 portions of the cloud trailed away in long streamers to 

 the south with one extensive branch going first north 

 by east, then north-westerly. 



At 3.50 P.M. there was another bright glow. As re- 

 gards the uprushes of steam the interval may not have 

 been constant, but it seemed to be about four to five 

 minutes. 



Towards 6 p.m. the bend over the steam column to 

 the north-north-west or north-west was more strongly 

 marked, and the asymmetry of the steam cloud was due 

 to a preponderating amount of steam gathering to the 

 north-west side of Erebus. By this time the older part 

 of the steam cloud had formed a species of thin cirrus 

 cloud, about 20,000 ft. to 30,000 ft. above sea-level. 



At 6.40 P.M. Shackleton observed a very bright glow 

 on the steam cloud. 



By 8 P.M. the eruption appeared to be subsiding, and 

 the steam cloud meanwhile stretched across the sky, now 

 in a direction from east-south-east to west-north-west (the 

 surface wind was at the time about north-north-east) , and 

 appeared to be passing almost over Sandy Beach and 

 Horseshoe Bay. It was now delicately draped in the form 

 of sinuous thin folds like a thin muslin skirt. Evidently 

 the wind direction had changed at the summit level to 

 about east-south-east to west-north-west. 



325 



