Spectra of Helium, fyc. in the Ultra-Violet. 297 



The dotted curves show the results obtained with the field 

 reversed, and serve as zero curves for eliminating the effects 



Fig. 6. — Radiation in Helium. 



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due to stray radiation. In fig. 6 A we have the same curves 

 corrected for this stray effect. These curves indicate that 

 the helium spectrum contains no detectable radiation shorter 

 than 425 x 10" 8 cm. Since there is a distinct effect at 



