314 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. $2 



In Potassium Vapor. 



Difficulty of experiment: 88(457) ; 85(463). 



Contains main and first and second sub-series of line spectrum: 85(463). 

 Doppler effect observed in case of doublet, XX 4044-47 distinctly: 85(463) ; 

 88(460); 89(112, 250). No intensity minimum. 

 8hift corresponds to singly charged potassium atom as carrier: 

 85(463); S9(ii2, 250). 

 In Illuminating Gas. 



Contains H lines, C line X 4267, N line X 3995, all very bright, also N 

 bands and 8viran bands which are rather weak: Kn3 (37). 

 Doppler effect shown by all lines, but by no bands: Kn3 (37). 

 In Acetylene. 



Contains H lines and C line X 4267, all bright. N, C, and 8wan bands 



are visible also: Kn3(36). 

 Doppler effect shown by all lines but by no bands: Kn3(36). 



X 4267 shows intensity minimum, shift points to singly charged C 

 atom as carrier: Kn3(36). 

 Spectrum in General. 



8pectrum is a part of that of gas in tube, same part as that of light from 

 first cathode layer, that is the series line spectrum : 

 Gi(696, 44); Win (132). 

 May contain lines of metal forming cathode: 8H(93). 

 May contain band spectrum of gas besides line spectrum, but the 

 latter is relatively more intense the greater the discharge 

 potential: SH(95). 

 Doppler Efeect in General. For summary see 823(828). 



Conditions to be satisfied to obtain effect: 818(231); 819(399). 

 Measurements only semi-quantitative because of inestimable errors : 



813(33, 179, 413, 438). 

 8hown by series line spectra of H, N, O, Na, K, and Hg: 85(461, 893), 

 perhaps also by O triplets: Sg3(i29) ; 823(821); 

 Ps4(998). Also by spectrum of He: 819(401) and of 

 Al: 823(822). 

 Not observed for any band spectrum. 

 Amount of shift serves to distinguish light from singly, doubly, and 



trebly charged atoms: 85(464, 894). 

 All lines of same series show same modified shift, AX/X, hence have 



same carrier: 813(33, 414). 

 Intensity minimum in general separates displaced from rest line : 

 810(252, 256) ; 813(31, 412, 179, 438) ; 819(399). 

 Width varies with gas and in any series varies with X ( ?) : 



821(799) ; Ps2(25o). 

 Less distinct the greater the pressure: Ew3(3i2). 

 Velocity corresponding to width of intensity minimum must be 

 exceeded by the canal rays or no displaced line will be 

 obtained: 813(180, 439); 818(232); 819(399); 820(64). 

 Minimum velocity varies for different gases and for different lines 

 in any series ( ?) : 821(799). 



