|THE STUDY OF STELLAR 
| EVOLUTION 
An Account of Some Modern Methods 
of Astrophysical Research 
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By Grorce Etrery HAte, Director of the 
Solar Observatory of the Carnegie Institution, 
Mount Wilson, California. 
“The Study of Stellar Evolution’ explains, 
in a popular way, how the life-histories of the 
sun and stars are investigated. A brief histori- 
cal sketch, in which the general purposes and 
methods of astrophysical research are outlined, is 
followed by several chapters on the sun, the only 
star that is near enough the earth to be studied 
in detail. An account of the spectroheliograph, 
which gives pictures of the sun, showing the 
flocculi—invisible clouds of calcium or iron vapor, 
or of hydrogen gas—introduces a series of chap- 
ters describing recent methods of solar and 
stellar research developed at the Yerkes and 
Mount Wilson observatories. 
250 pages 104 plates 8vo, cloth Postpaid, $4.27 
The University a Chicago Press 
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