88 THE INDIAN ECLIPSE, 1898. 



It was not altogether unnatural that there was a reluctance 

 to accept the corona as truly solar until it had been proved to 

 be such by the clearest demonstration. For if it belonged to 

 the sun, its extent must be counted even by millions of miles, 

 and it must form a structure of a vastness beyond the powder of 

 man's imagination to truly appreciate. Yet the proof that it 

 was solar had been supplied as early as 1724 by Maraldi, who 

 observed that the corona did not travel with the moon but was 

 traversed by it ; but this deduction found no general acceptance 

 until the eclipse of 1851, and some astronomers held out against 

 it for two decades longer. 



The earliest drawings made of the corona are very curious. 

 They give it the form of a Greek cross four equal arms at 

 right angles to each other. Two drawings preserved to us in 

 1715, and a third in 1766, and reproduced in the great eelipse 

 volume published by the Royal Astronomical Society, vol. 41 

 of their Memoirs, well illustrate this peculiarity. Later we find 

 the tendency of the drawings to run into general halos, the 

 desire of the artists evidently having been rather to suggest the 

 general effect than to delineate precisely the form and structure 

 of the corona as they actually saw it. 



From 1851 onwards we have a large number of drawings 

 which were evidently made w T ith due care and conscientiousness. 

 They are not always easy to collate together, because, as eyes 

 differ in sensitiveness and as atmospheric conditions differ from 

 place to place, so the form and extent of the corona as drawn 

 by different observers in the same eclipse vary exceedingly. A 

 striking instance of this was afforded in the eclipse of 1874, 

 April 16, when two observers, Mr. Henry Hall and Miss Alice 

 Hall, seated side by side at the same table, drew the corona 

 with results which did not bear the slightest resemblance the 

 one to the other, Mr. Hall tracing the outline of the corona to 

 not quite eleven minutes from the moon's limb, whilst his sister 

 traced it in one direction nearly ten times as far. Fortunately 

 before the eclipse was over they were able to compare notes, and 

 it became clear that whilst Mr. Hall had drawn the outlines of 

 the brightest and innermost portion of the corona, his sister 

 had endeavoured to depict the shape of its faint outer extensions. 



The eclipse of 1 870 was well observed in Spain and Sicily, 

 and that of 1871 in India and elsewhere, and a valuable harvest 

 of drawings and photographs was secured. The next eclipse 

 that was observed with anything like the same fulness fell in 

 1878, the track then lying across the American continent and 

 calling forth a great army of skilled observers. It was at once 

 seen that the corona of 1878 w T as utterly unlike in form those 

 of 1870 or 1871. In the two earlier years it had had the form 

 of a great irregular halo, sending out its rays indiscriminately 

 in almost every direction round the sun. In 1878 there was a 



