OBSERYATIONS AT THE SUMMIT OF MONT BLANC. 243 



impossible; but of that tliere was no need, since the succession of these 

 scenes remained engraved ineffaceably upon my mind. 



Why are the emotions so lively? Why, in ijarticular, during the 

 four nights I passed at the summit did I experience a feeling- of such 

 delicious buoyancy throughout my being? Why did it seem that 1 

 was relieved of a great weight which till then had fettered and weighed 

 down my mind, and that it was now to take its flight and ox)eu in full 

 liberty and love the questions the hardest and the finest of a higher 

 moral order ? 



Is it the simple effect of the small specific gravity of the air of those 

 high altitudes? Do there not enter other causes still unknown which 

 shall be investigated in the future? 



Be this as it may, it seems that nature, which does nothing in vain, 

 and which is full of these harmonies, wishes to prepare us by the very 

 effect of these high altitudes to better feel the greatness and the sub- 

 ■ limity of the scenes that it presents to us.^ 



But the sun rose brightly the next morning, while I was present as 

 spectator of an event less dramatic than the setting of the previous 

 evening, but still of a grandeur unparalleled. I could give it, however, 

 but a few moments' attention. I wished to profit by the presence of 

 this fine sun to execute the long and delicate observations which I had 

 not been able to make with my large instruments at the time of my 

 ascent of 1890. 



Those observations related, as is known, to the vexed question of the 

 presence of oxygen in the gaseous elements of the sun. 



The eminent American physicist, Draper, thought himself able to 

 conclude from observations of spectral jjhotography that oxygen was a 

 part of the solar atmosphere. Now this question of solar oxygen has 

 an importance which transcends the purely scientific horizon. 



If the sun is so constituted as to fill for long ages its office of dis- 

 penser of heat and light to the worlds it enchains around it, science 

 foresees, nevertheless, that by the inevitable effect of time its radiating 

 powers will diminish and more and more decline. Now if, during the 

 ages which shall witness this lowering of temperature, the gaseous 

 envelopes so rich in hydrogen surrounding the incandescent orb were 

 to contain oxygen besides, a moment would necessarily be reached in 

 which a combination of the two bodies would take j)lace, and then enor- 

 mous quantities of aqueous vapor would appear in the solar atmosphere. 



Now, we know that the vapor of water is that one of the elastic 

 fluids that is endowed with the most energetic power of absorption 

 for radiant heat. This aqueous atmosphere would, then, form a veil, a 



' I here repeat what I have already said apropos of the ascent of 1890, that this 

 state of mind supposes that one has nothing to do in the way of physical effort. In 

 my opinion, it is the mode of going up I employed and the care I took to preserve 

 all the forces of my intellectual life which put me into the state of mind shown in 

 the above passages. 



