THE MASTER KEY OF SCIENCE: REVEALING THE 

 UNIVERSE THROUGH THE SPECTROSCOPE ^ 



By Henry Noeeis Russell 

 Professor of Astronomy, Princeton University 



[With 2 plates] 



The great French philosopher of the last century, Auguste Comte, 

 was an exceedingly well-informed and versatile man, but it was he 

 who once remarked : " There are some things of which the human 

 race must forever remain in ignorance; for example, the chemical 

 composition of the heavenly bodies." To Comte and the other intel- 

 ligent men of his time, this problem seemed hopelessly insoluble; 

 there was no way of attacking it. 



Of course this statement sounds ridiculous to us now. It became 

 ridiculous because man's dream came true of a master key that 

 would unlock many doors, one after another, and so open up many 

 new realms of knowledge. 



That master key was the spectroscope. No sooner was it discovered 

 than the composition of the heavenly bodies, previously unknowable, 

 became an open book. With its use, many of the familiar chemical 

 elements were identified in the sun, and not long after, in the stars. 

 Later work has extended the number of elements identified in the 

 sun to 60, and spectroscopic study has shown that the atmosphere 

 of Mars contains oxygen and water vapor, while that of Venus shows 

 no signs of them. 



All the stronger lines in the spectra of the sun and stars and a host 

 of the weaker ones have been identified. It has been demonstrated 

 that the same atoms are present on earth that are also present in 

 the remotest nebulae, in the relatively cold tail of a comet, and in 

 the intensely heated surface of a white star. By showing these 

 things, the spectroscope has given the most impressive of all proofs 

 of the unity of nature. 



This achievement has been described in poetry, as it should be, 

 by Edmund Clarence Stedman, in one of his more philosophical 



1 An addiess delivered at the inauguration of the spectroscopic laboratories of tlie 

 Massachusetts Institute of Technology, Feb. 25, 1932. Reprinted by permission from 

 Technology Review, April, 1932. 



133 



