The extreme tenuity of the stellar atmosphere appears to be unquestionably established by the data set forth above, and a maximum effective pressure of
may therefore be assumed in a discussion of the spectra of reversing layers.
| Pressure Shifts | less than |
| Line Sharpness | less than |
| Line Width | |
| Flash Spectrum | |
| Radiative Equilibrium | order of |
| Limit of Balmer Series | to (upper limit) |
| (Ionization | to ) |
FOOTNOTES:
[58] Eddington, Zeit. f. Phys., 7, 731, 1921.
[59] Pannekoek, B. A. N., 19, 1922.
[60] Milne, Phil. Mag., 47, 217, 1924.
[61] Ap. J., 42, 271, 1915; Princeton Contr. No. 3, 82, 1915.
[62] M. N. R. A. S., 83, 403, 1923.