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From Newton to Kirchoff. 



a constituent of the sun ! Upon the foundation thus laid by 

 Kirchoff, the science of celestial chemistry has been built. 



Newton, Fraunhofer, Melville, Wheatstone, Kirchoff — 

 these names mark the five remarkable stages in a journey 

 of two hundred years duration, through which science has 

 been brought to the summit of so high a range, that look- 

 ing out upon the heavens she can declare the composition 

 of the sun and stars. 



