400 
APPENDIX II 
Electrical Forces and Diffusion in the Interior. 
The subject is treated by 
32. S. Chapman. Convection and Diffusion within Giant Stars. Monthly Notices , 
11, p. 541 (1917). 
33. S. Chapman. Diffusion and Viscosity in Giant Stars. Monthly Notices, 82, 
p. 292 (1922). 
34. S. Rosseland. Electrical State of a Star. Monthly Notices, 84, p. 720 (1924). 
35. E. A. Milne. Dissociative Equilibrium in an External Field of Force. Proc. 
Camb. Phil. Soc. 22, p. 493 (1925). 
36. S. Rosseland. On the Distribution of Hydrogen in a Star. Monthly Notices, 
85, p. 541 (1925). 
The section of the book dealing with this subject (§§ 191-196) was written 
before the last three papers appeared; they were available for the final revision. 
Circulating currents are suggested in No. 22, and in 
37. H. Vogt. Zum Strahlungsgleichgewicht der Sterne. Astronomische Nachrichten, 
No. 5342 (1925). 
The theorem leading to this inference is contained in 
38. H. von Zeipel. Zum Strahlungsgleichgewicht der Sterne. Festschrift fur H. 
von Seeliger, p. 144 (1924). 
A criticism by Jeans is answered by von Zeipel in Monthly Notices, 85, p. 678. 
Rotating Stars. 
Detailed investigations are given by 
39. E. A. Milne. The Equilibrium of a Rotating Star. Monthly Notices, 83, p. 118 
(1923). 
40. H. von Zeipel. The Radiative Equilibrium of a Rotating System of Gaseous 
Masses. Monthly Notices, 84, pp. 665, 684, 702 (1924). 
The Outside of a Star. 
The classical papers are (in addition to reference No. 2) 
41. A. Schuster. Radiation through a Foggy Atmosphere. Astrophys. Journ. 21, 
p. 1 (1905). 
42. M. N. Saha. On a Physical Theory of Stellar Spectra. Proc. Roy. Soc. 99 A, 
p. 135 (1921). 
Chapter xn is based in large measure on E. A. Milne’s researches. We divide 
our selected references under the headings (a) Photosphere, (6) Chromosphere, 
(c) Reversing Layer. 
(a) Photosphere. 
43. K. Schwarzschild. Ueber Diffusion und Absorption in der Sonnenatmosphare. 
Berlin. Sitzungsberichte, 1914, p. 1183. 
44. J. H. Jeans. The Equations of Radiative Transfer of Energy. Monthly Notices, 
78, p. 28 (1917). 
45. E. A. Milne. Radiative Equilibrium in the Outer Layers of a Star. Monthly 
Notices, 81, p. 361 (1921). 
46. E. A. Milne. Radiative Equilibrium and Spectral Distribution. Monthly 
Notices, 81, p. 375 (1921). 
47. E. A. Milne. The Effect of a strong Absorption Line. Monthly Notices, 81,. 
p. 510 (1921).