ORIGIN OF ROCKS. 97 



attenuated forms ; for the new laws discovered by chemists 

 recently as regards the doctrine of dissociation of bodies by 

 heat, leads to the belief that these rocks have been evolved 

 from some common primal matter, which pervades the whole 

 vast universe, and of the nature of which we have no knowl- 

 edge. It is singular that this view approximates those held 

 by Lavoisier, the ftither of chemistry, nearly a century ago. 

 This most sagacious philosopher and experimenter stated that 

 it was possible that all matter might be resolved into only 

 three forms, — oxygen, hydrogen and nitrogen ; and, certainly, 

 I find the idea of great simplicity in the constitution of 

 matter is gaining ground among modern chemists every day. 

 The results of spectrum analysis go to prove the correctness 

 of this view. And here, let me say, that quite all we know 

 of celestial chemistry results from researches made with 

 that marvellous instrument, the spectroscope. We find from 

 its revelations, that, in the chromosphere of the sun, there 

 exist materials like those which exist upon our planet. But, 

 in addition to the iron, calcium, magnesium, and a dozen 

 other elements in the sun, we find there is another shown in 

 the spectrum which is not recognized as belonging to any of 

 the terrestrial elements. This is shown by a green line in the 

 spectrum. When the spectroscope is directed to the fixed 

 stars, Ave get some very interesting results ; and the same 

 may be said in regard to the nebulae. It appears that the 

 nebulous matter which is floating through space, is made up 

 of only two elementary forms of matter, and those the most 

 attenuated, — nitrogen and hydrogen. Now, if it is true that 

 these nebulous masses which are floating in the interstellar 

 spaces are the first beginnings of worlds, a difiiculty presents 

 itself, unless the large number of our terrestrial elements are 

 capable of being evolved from the two or more revealed to us. 

 A world, according to our notions, could not be perfect unless 

 it held our sixty-five elements. If we apply the spectroscope 

 to the fixed stars of different colors, — the white, the yellow, 

 and the red, — we there find the history of worlds in their for- 

 mative stajre revealed in a most remarkable manner. The 

 spectroscope applied to the light which comes from the dog- 

 star, Sirius, which is a white star, proves that all elementary 

 forms of matter existins' there are the most attenuated. We 

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