ABOUT THE ATMOSPHERE AND ITS rHENOMENA. 717 



atnre as to hold many of our solids in a state of vapor, because, from their 

 great mass, the cooling process has not reached the stage it has with us. 

 And from all indications Jupiter is now in the condition described for our 

 earth, in the period of the vapory condensation and rains. The moon shows 

 no atmosphere that is perceptible from our methods — because from her size 

 she must have so cooled as to condense all her matter — that her rocks have 

 absorbed the oxygen and nitrogen, as the process is now going on in the 

 nitre beds of our earth. This is not only possible, but by the law of 

 planetary development must be so, from the properties of the atmosphere 

 itself — for its most prominent physical property is that it is expanded by 

 heat and condensed by cold — the latter if intense enough reducing all things 

 to solids — and then the end. In degree wo see this quality before us 

 every day proclaiming the law. 



That the atmosphere is the result of this condensation, or rather remains 

 as that portion of the original mass which refuses the solidifying agencies, 

 has support in the nature of the elements themselves. No agent, no re- 

 source has yet been found in chemistry powei-ful enough to change the 

 conditions of pure nitrogen and oxygen. Nitrogen not only resists all 

 efforts to change its form, but to unite it with other substances. It is per- 

 sistent and unchangeable by any known appliance. Why then may it not 

 be the result, or rather the residuum, of the forces which have transformed 

 our earth from a glowing ball to the beneficent world we find it? And so 

 of oxygen, another obdurate element, a little less so than nitrogen, therefore 

 less in volume, and combining with hydrogen to form water; abundant in 

 all matter, and when subject to the forces of nature, producing a concen- 

 trated form of itself, called ozone. Following the cosmic law; accepting the 

 universally received hypothesis of the origin of the solar system, and its 

 formation — can we account for the existence of the atmosphere upon any 

 other theory than this ? It seems from the premises logically inevitable. 



That it is so analogy teaches— for in excess of either oxygen or nitrogen, 

 life becomes impossible, beyond given quantities. And that the time was 

 when they were in excess, we have abundant evidence, as in the case of 

 nitrogen even, in the saltpetre caves and the vast nitre beds of some parts 

 of the world, in which this stubborn element is imprisoned by a force greater 

 than we know, and the oxj'-gen in its varied combinations. When so re- 

 duced in volume, life as it exists was possible, and it came when the place 

 was prepared for it. 



If, then, this is the origin of the atmosphere, it suggests another thing. 

 Being a part of the original matter of the earth, differing only in state from 

 inherent properties of its own — being obdurate in the direction of solids 

 while others are facile — it must not only be influenced by the same forces 

 that influence the solid portions of the planet, but it must support its share 

 of the circulating forces which give life and potency to it. And that it is 

 so we gather in many ways. 



Besides these two principal elements, we find in the air carbonic acid, 



