294 Journal of the Asiatic Society of Bengal. [Sept., 1915. 
black ‘‘umbra,’’ looking as if fine lines had been drawn from 
centre to circumference. This is one of the most striking 
spectroscopic investigation at Kodaikanal has shown that it 
Magnetic needles are closely connected with the suns 
cycle. This cycle, during which the number and activity 
sunspots waxes and wanes in an average period of eleven years, 
Obse 
Mais calcium light, with a screen to shut out the light i 
© disc; and thus we obtain records of the uprusbi0é *" 
composed of hydrogen and calcium which are always forms 
