988 



THE NATIONAL GEOGRAPHIC MAGAZINE 



mountain an immense depression marks 

 the site of the old crater, and from the 

 side of this rises the active cone, gen- 

 erally marked by steam or smoke. The 

 ascent of such a mountain would be a 

 matter of difficulty in any part of the 

 world, hardly to be attempted without 

 experienced guides, but the difficulties 

 were accentuated by the latitude of 

 Erebus. 



The observer taking the meteorological 

 observations every two hours had the 

 mountain in sight, and as Erebus was our 

 high-level meteorological observatory, to 

 the crown of which we always looked 

 for indications of wind-currents at that 

 elevation, we naturally saw every phase 

 of activity produced by the fires within. 

 It was for this reason, no doubt, that 

 during the period of our stay in these 

 regions, more especially through the win- 

 ter months, we were able to record a 

 fairly constant condition of activity on 

 the mountain. It became quite an ordi- 

 nary thing to hear reports from men who 

 had been outside during the winter that 

 there was a "strong glow on Erebus." 

 These glows at times were much more 

 vivid than at others. On one particular 

 occasion, when the barometer showed a 

 period of extreme depression, the glow 

 was much more active, waxing and wan- 

 ing at intervals of a quarter of an hour 

 through the night, and at other times we 

 have seen great bursts of flame crowning 

 the crater. 



The huge steam column that rises from 

 the crater into the cold air shot up at 

 times to a height of 3,000 or 4,000 feet 

 before spreading out and receiving its 

 line direction from the air-currents at 

 that particular hour holding the upper 

 atmosphere. There were occasions when 

 the view of this steam cloud became 

 much more vivid, and we found that the 

 best view that could be obtained was 

 when the moon, rising in the eastern 

 sky, passed behind the summit of the 

 mountain. Then, projected on the disc 

 of the moon, we could see the great cloud 

 traveling upward, not quietly, but im- 

 pelled by force from below. 



There were times also when it was 



obvious that the molten lava in the crater 

 could not have been very far from the 

 lip of the cup, for we could see the 

 deep-red glow reflected strongly on the 

 steam cloud. We often speculated as to 

 the course the lava stream would take 

 and its probable effect on the great 

 glaciers and snow-fields flanking the sides 

 of the mountain, should it ever overflow. 

 These sudden uprushes were obviously 

 the result of a vast steam explosion in 

 the interior of the volcano and were suf- 

 ficient proofs that Erebus still possesses 

 considerable activity. 



THE ASCENT OF EREBUS. 



Before the winter set in, several mem- 

 bers of the party climbed to the summit 

 of Erebus. Their achievement will rank 

 high among mountain climbs, for the 

 party was compelled to endure tempera- 

 tures of below zero, to fight through 

 raging blizzards, and often the ascent 

 was so steep as to be nearly insurmount- 

 able. From the summit they could look 

 down into the fiery chasm of the vol- 

 cano. 



"We stood on the verge of a vast 

 abyss, and at first could see neither to 

 the bottom nor across it on account of 

 the huge mass of steam filling the crater 

 and soaring aloft in a column 500 to 

 1,000 feet high. After a continuous loud 

 hissing sound, lasting for some minutes, 

 there would come from below a big dull 

 boom, and immediately great globular 

 masses of steam would rush upward to 

 swell the volume of the snow-white cloud 

 which ever sways over the crater. This 

 phenomenon recurred at intervals during 

 the whole of our stay at the crater. 

 Meanwhile, the air around us was ex- 

 tremely redolent of burning sulphur. 

 Presently a pleasant northerly breeze 

 fanned away the steam cloud, and at once 

 the whole crater stood revealed to us in 

 all its vast extent and depth. 



"Mawson's angular measurement made 

 the depth 900 feet and the greatest width 

 about half a mile. There were at least 

 three well-defined openings at the bot- 

 tom of the cauldron, and it was from 

 these that the steam explosions pro- 



