﻿Elements of the Higher Grovps. 1139- 



The lines of N ++ are very prominent in the spectrum of 

 No v?e in their later stages simultaneously with He + 4686. 

 and C++ 4650-8, 4647-0. 



Nitrogen, having 5 electrons in the outer shell, would 

 have a large u steric factor " for not only the neutral atom, 

 but also for N + and N ++ , which probably accounts for the 

 quick succession of the different stages of ionization. 



According to Lockyer *, Protovanadium or V + , as repre- 

 sented by the line X = 4053*9, is strongly developed in F5A 

 stars, but shows a weakening in Ao-stars, and disappears 

 somewhere about the B8-stage. In the stellar ranges we 

 have, therefore, V, V + , and V + + in rather quick succession. 



It will be seen that the above discussion mainly centres 

 round the life-work of the late Sir Norman Lockyer. To him 

 is due not only the idea, but also extended and elaborate 

 studies of the enhanced and super-enhanced lines of elements,. 

 and their application to the study of the ordered sequence in 

 stellar spectra. In this connexion, attention may be drawn 

 to the views which he presented in his ' Inorganic Evolution 

 of Elements/ He tried to impress the idea that the enhanced 

 lines are due to some proto-form or fractional part of 

 chemical atoms. But in those days the atom was an u elastic 

 solid sphere/' and his ideas did not find many adherents. 

 The real significance of his works is being realized in these 

 days of the Rutherford-Bohr theory of atomic constitution. 



The present paper probably brings out the great importance 

 of these studies to problems of atomic physics. Lockyer's 

 studies have been continued by American and English 

 workers, but the data hitherto available are not sufficient tor 

 the purpose. The above discussion, though scrappy, prob- 

 ably points out the direction in which these studies ought to 

 be extended and amplified. 



Note added during correction. — Since the paper was written, 

 Russell has published a paper in the Astro. Journal, May 

 1922, where he has modified the view that Ba is absent from 

 the sun. The 1S-3P line of Ba (\ = 3071*59) has been 

 identified with a line of intensity 00, the resonance line 

 X = 5535 being probably masked by an iron-line at 

 X= 5535-68. 



* Proc. Roy. Soc. Lond. vol. lxiv, p. 396 ; Phil. Trans. " On the 

 Spectrum of a Cygnus," 1903. 



