Smithsonian Report. 1940. McMath 



Plate 3 





Formation of Prominence. September 23. 1938. Ha Spectroheliograms. 



A, lSh3.03"'; B, 19^ 1 2.-,. ]<•'■. C. l<Ji'12.3i:'"; D, 19l'47.77": E. 19h53.99"'; F, 2l|h!l.(i2N.; (:, 2(|i'7 32" • // 20i>10 69" 



a.c.T. 



