NO. 1863 BIBLIOGRAPHY OF CANAL RAYS — FULCHER 315 



Intensity of displaced line obeys different laws from that of rest line 

 increasing with the velocity of the rays: 818(232). 

 Displaced intensity varies with gas and, in any series, with X : 



813(176, 434); 820(63). 

 Ratio of stationary to displaced intensity same on any one spectro- 

 gram for all lines of one series: 813(182, 441). 

 8tationary intensity appears to vary in step with that of band spec- 

 trum, increasing with the pressure: 813(175, 434). 

 Absence of Doppler effect in some cases not well understood: Hl4(ii9). 



Shift of Lines Toward Red, observed with collimator perpendicular to rays. 

 Definitely observed on all spectrograms taken, determined by measuring 



the position of lines in question with reference to certain 



band lines, most probably unshifted: S7 ; 88(107); 



813(191, 452). 

 Amount 0.7 A for H^ with 8,000 v.: 813(194, 453). 

 No shift observed by Hull for H or Hg lines: Hli; Hl2(i9). 

 Apparent shift may be due to error in setting collimator and may be the 



Doppler effect: 813(189, 450). 



Broadening of Lines observed with collimator perpendicular to rays. 



H lines greatly broadened, most just behind cathode: Hli; Hl2(i9). 

 Broadening increases with velocity, shorter wave lengths broaden 

 more rapidly: 87; 88(107); 813(190, 451). 

 Also with pressure: 8(42, 423). 

 Partly a Doppler effect: 813(191, 452), 



Less than Doppler effect in the ratio, velocity of rays to that of light : 

 88(109). 

 Hg lines show slight broadening: Hli. 

 He lines show no broadening: Hl2(i9). 



14. PARTIAL POLARIZATION OF LIGHT. 



81ight effect reported by Stark in case of H lines, vibrations parallel to rays 

 being more intense than those perpendicular to their 

 direction, difference very small and difficult to observe : 

 S7; 88(105, 106) ; 818(230). 



No polarization as great as one-half per cent of light was detected by Hull, 

 using optical glass window and very sensitive Nicol 

 prism and Savart plate: Hli; Hl2(i7) ; Hl3(234). 



