Here they found a small aperture which appeared to have been recently formed—­probably by a blow from a mass of falling rock—­through which they were able to obtain a glimpse of the pandemonium that lay seething below them.  They could not see much, however, owing to the smoke which filled the air.  The noise of the almost continuous explosions was so loud, that it was impossible to converse save by placing the mouth to the ear and shouting.  Fortunately soon after their ascent the wind shifted and blew smoke, fire, and dust away to the northward, enabling them to get out on the ledge, where for a time they remained in comparative safety.

“Look! look at your mirrors!” exclaimed Nigel suddenly, as his wandering gaze happened to turn to the hermit’s sun-guides.

And he might well exclaim, for not only was the glass of these ingenious machines shivered and melted, but their iron frameworks were twisted up into fantastic shapes.

“Lightning has been at work here,” said Van der Kemp.

It did not at the moment occur to either of them that the position on which they stood was peculiarly liable to attack by the subtle and dangerous fluid which was darting and zig-zagging everywhere among the rolling clouds of smoke and steam.

A louder report than usual here drew their attention again to the tremendous scene that was going on in front of them.  The extreme summit of Perboewatan had been blown into a thousand fragments, which were hurtling upwards and crackling loudly as the smaller masses were impelled against each other in their skyward progress.  This crackling has been described by those who heard it from neighbouring shores as a “strange rustling sound.”  To our hermit and his friend, who were, so to speak, in the very midst of it, the sound rather resembled the continuous musketry of a battle-field, while the louder explosions might be compared to the booming of artillery, though they necessarily lose by the comparison, for no invention of man ever produced sounds equal to those which thundered at that time from the womb of Krakatoa.

Immediately after this, a fountain of molten lava at white heat welled up in the great throat that had been so violently widened, and, overflowing the edges of the crater, rolled down its sides in fiery rivers.  All the other craters in the island became active at the same moment and a number of new ones burst forth.  Indeed it seemed to those who watched them that if these had not opened up to give vent to the suppressed forces the whole island must have been blown away.  As it was, the sudden generation of so much excessive heat set fire to what remained of trees and everything combustible, so that the island appeared to be one vast seething conflagration, and darkness was for a time banished by a red glare that seemed to Nigel far more intense than that of noonday.

It is indeed the partiality (if we may say so) of conflagration-light which gives to it the character of impressive power with which we are all so familiar—­the intense lights being here cut sharply off by equally intense shadows, and then grading into dull reds and duller greys.  The sun, on the other hand, bathes everything in its genial glow so completely that all nature is permeated with it, and there are no intense contrasts, no absolutely black and striking shadows, except in caverns and holes, to form startling contrasts.