396 Proceedings of Royal Society of Edinburgh. 
[sess. 
Photographs of the Corona taken during the Total 
Solar Eclipse of May 28th, 1900. By Thos. 
Heath, B.A. (With Five Plates.) 
(Read July 15, 1901.) 
In June of last year I had the honour of reading before this 
Society a preliminary account of the Scottish expedition for the 
observation of the Total Solar Eclipse of May 28th, 1900, at Santa 
Pola, on the south-east coast of Spain (long. 0° 30' W., lat. 
38° 13' N.). I have now to lay before the Society the results 
of the part of the expedition specially assigned to me, which 
was to obtain photographs of the Corona. I succeeded in securing 
four, that being the largest number I considered it advisable to 
attempt in the very short total phase of eclipse, only 75 seconds 
being available for the exposures and necessary manipulation of 
the camera backs. 
According to my original plan, I had arranged to expose the 
four plates as follows : — The first immediately after totality com- 
menced, with an exposure of 1 second ; for the second I allowed 
an exposure of 6 seconds; for the third, 15 seconds; and for the 
fourth, 1 second. For each of the three intervals between 
successive exposures necessary for turning the backs, closing and 
opening the slides, etc., I found I had to allow 15 seconds. 
I drilled myself for several days before the eclipse, till I found I 
could get through my programme quite comfortably in the time 
allotted to each part, and finish with my fourth plate exposed a 
few seconds before totality ended. In the agitation which is 
almost inseparable from the supreme moment of an eclipse, I 
suppose I must have made some of my intervals rather longer than 
I had arranged, with the result that my last plate appears to have 
been exposed at the critical moment when the sun was just 
beginning to reappear outside the western limb of the moon. This 
fact is well shown on the photograph. The presence of the sun 
has not, however, in any way interfered with the success of the 
