8 Turner, Total Solar Eclipses. 



region near the French convict settlement at Cayenne. 

 Perhaps if it had been known beforehand how bad the 

 conditions really were the expedition might have been 

 abandoned, but this was not realised until too late. He fell 

 ill with dysentery, and although he successfully completed 

 the work for which he was sent out, he shortly afterwards 

 died at sea. He was ill on the actual day of the eclipse — 

 so ill that when the observations were completed, and he 

 called for three cheers for the success, he was unable to 

 join in them himself. " I can't cheer," he said, "but I will 

 wave my helmet." It is a memory worth preserving, — 

 that a brave swimmer caught by the cruel waters of 

 disease should go down waving his helmet for the success 

 which had cost him his life. 



So great a disaster is fortunately rare in scientific 

 work ; but hardship must often be faced, and disappoint- 

 ment is always risked, on eclipse expeditions, which have 

 for their object the best utilisation of the few precious 

 moments during which the corona is visible. It might be 

 difficult to justify this enthusiasm from the cold, logical 

 standpoint of actual knowledge : we do not know that the 

 Corona is the most important part of the sun ; indeed from 

 what we know up to the present, it may be comparatively 

 unimportant. But the other extreme is also possible ; the 

 study of the Corona may give us an invaluable clue for 

 interpreting other solar phenomena, and this very uncer- 

 tainty is in itself attractive. In any case it scarcely needs 

 explanation that a phenomenon which can only be observed 

 for a few hours altogether in a whole century, should 

 attract more than its strictly logical share of attention. 

 At any one place a total eclipse lasts a few minutes only, 

 say two minutes on the average. Now there are twelve 

 "families" of total eclipses which recur in a regular cycle 

 every i8 years, ii| (or I2i, according to the occurrence 



