54 THE BORDERLAND OF SCIENCE. 



tremendous hurricanes. But even as we watched, the 

 explosions grew less fierce. Presently they ceased ; and 

 then the whole prominence, vast as was its extent, 

 seemed to dissolve, until in an incredibly short time 

 no trace of it could be perceived. 



But a circumstance that surprised us greatly was this. 

 Although the uproar and tumult which prevailed were 

 inconceivably great, yet, during the whole progress of the 

 solar eruption which we had been witnessing, there were 

 no sounds which we could associate with the tremendous 

 outbursts which must in reality have taken place. Ac- 

 customed to associate terrestrial volcanic explosions 

 with sounds of exceptional loudness, we were amazed 

 to perceive no distinctive sounds during the infinitely 

 mightier eruption we had just watched. 



But as we passed towards the scene of the eruption 

 eager to contemplate the effects of an outburst com- 

 petent to destroy the whole frame of a globe like the 

 earth the mystery was explained. While we were still 

 far from the place of explosion, and intent on the study 

 of the great facular waves which were passing swiftly 

 beneath us, we suddenly heard a series of explosions so 

 tremendous that we imagined a new eruption was com- 

 mencing close by. Yet we could perceive no signs of 

 unusual solar activity. All round our horizon, indeed, 

 we could discern prominences of greater or less dimen- 

 sions : but these we had observed before. Whence then 

 came the fearful noises now reverberating through 

 the solar atmosphere ? noises so tremendous, that the 

 unutterable uproar which had prevailed unceasingly all 



