136 Progress in Science. (January, 
When examined with the spectroscope its fluorescent light emitted by the 
solid yields a sys ae m of eight bands. Of these the 1st and 7th are very 
Fic. g. 
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Fic. 12 
emeneeerncema 
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faint, and the 8th only appreciable with a strong light and wide opening to the 
slit of the spectroscope. The brighter bands show a very setae termination 
