330 



Mr Filon, On the variation with the wave-length 



Table VII. S 57. 



Remarks on S 57. 



A. June 23 (afternoon). Central diaphragm. 



B. „ „ (morning). 



C. July 9. Diaphragm adjusted to give same l 

 that obtained when no diaphragm is put in. 



D. July 10 (morning). No diaphragm used. 



E. July 10 (afternoon). Central diaphragm. 

 [Only the first extinction was observed.] 



eading 



as 



