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X. A Critical Study of Spectral Series. Part V. The Spectra of the 



Monatomic Gases. 



By W. M. HICKS, F.R.H. 



Eeceived November 14, 1918, Read January 23, 1919. 



[PLATES 2-5.] 



CONTENTS. 



Page 



Introduction 336 



Krypton, S series 344 



links 347 



,, double displacements 349 



Xenon, S series 350 



variability with excitation 350 



,, links 352 



Argon, S series 355 



links 357 



,, examples of displacement, 359 



D and F series 360 



Krypton, D series 361 



abnormal D separations 363 



satellites 365 



F series 368 



P 375 



,, value of the oun 377 



Xenon, D series .... 381 



F and P series 383 



source of 1864, 829 separations 393 



D series resumed 396 



D qualification test 397, 406 



existence of parallel D groups .... 399 



satellite sets 402 



two groups depending on 79 A s , 70 A 2 404 



parallel F and P series 411 



Ritz combinations .... 421 



value of the oun 421 



VOL. CCXX. A 580. 3 A [Published May 19, 1920. 



