The heavens above: a popular handbook of astronomy (1882)
Gillet, J. A. (Joseph Anthony), 1837-1908 · New York, Chicago, Potter, Ainsworth, & Co. · leaf 215
Fig. 211. dissociated elsewhere on the suns surface. These lines andshadings are shown in Fig. 211. It often happens that certain of the spectral lines are re-versed in the spectrum of the spot, a thin bright line appear-ing over the centre of a thick dark one, as shown in Fig. 212.These reversals… … At times, also, the spectrum of a spot indicates violent motion in the overlying gases by distortion and displacement of the lines. This phenomenon occurs oftener at points near the outer edge of the penum-bra than over the centre ofthe spot; but occasionally thewhole neighborhood is vio-lently…
Astronomy
Internet Archive · Cornell University Library · Public Domain Mark 1.0. Free to use for anything.