THE LIGHT OF THE STARS. 171 



Secchi's third type, or red stars, represented by 

 Betelgeux, Antares, and others, are characterised 

 by strong absorption bands, and the spectra have 

 been described as " fluted." The third- type stars 

 are comparatively scarce compared with the first 

 and second, and the fourth is even less numerous. 

 The fourth -type stars are also red with broad 

 absorption lines. To Secchi's four types a fifth 

 was added in 1867 by Wolf and Rayet of Paris 

 Observatory namely, the gaseous stars. Secchi 

 aimed at a comprehensive survey of the stellar 

 spectra, and he accomplished much valuable 

 work. He did not devote his time to analys- 

 ing individual stars. This branch of study 

 analysis of spectra and the determination of the 

 elements in the stars was undertaken by his 

 contemporary, William Huggins, one of the 

 greatest astronomers whom England has ever 

 produced. 



Born in London in 1824, William Huggins 

 commenced his astronomical researches at the 

 age of twenty -eight. In 1856 he erected, at 

 Tulse Hill, London, an observatory which he 

 equipped at great expense. He commenced 

 observations on the usual astronomical lines, 

 taking times of transits and making drawings 

 of the surfaces of the planets. But he soon 

 tired of the routine of ordinary astronomical 



