94 Master Minds of Modern Science 



of the disc of the darkened sun. Of these the most 

 interesting is that of the eclipse watched on May 20, 1919, 

 at Sobral, in Brazil, which definitely proved Einstein's 

 theory that light was bent in passing through a magnetic 

 field. 



Sir Frank Dyson himself has been on several of these 

 expeditions to observe total eclipses. On one occasion, 

 with a party of astronomers, he was taken to Morocco 

 in a cruiser, the Suffolk, and he mentioned the fact 

 that the present Admiral Beatty was then captain of 

 the ship. 



Sir Frank, through whose kindness this chapter has 

 been made possible, is a Fellow of Trinity College, Cam- 

 bridge, where he was Second Wrangler and Smith's 

 Prizeman. He was Chief Assistant at Greenwich from 

 1894 to 1905, and then became Astronomer Royal for 

 Scotland. In 1910 he went back to Greenwich as 

 Astronomer Royal, a position which he has now held for 

 twenty years. 



