236 Proceedings of Royal Society of Edinburgh. [sess. 
The Total Solar Eclipse of 28th May 1900. 
By Thomas Heath, B.A. 
(Read June 18, 1900.) 
The Scottish Expedition to observe the Total Solar Eclipse of 
May 28 consisted of Professor Copeland and Mr J. B. MTherson, 
Engineer to the Boyal Observatory, Edinburgh, who were sent 
out by the Joint Eclipse Committee of the Boyal and Boyal 
Astronomical Societies; Mr Franklin-Adams, who joined the 
party as a volunteer observer ; and myself, who had the honour 
of being sent out by this Society. The special object which 
we had set before ourselves was, of course, the attempt, if possible, 
to add something, however little it might be, to the sum of known 
facts concerning the constitution of the solar corona. This 
problem, as I need not remind this Society, has occupied the 
minds of all students of solar physics for many years, and has 
formed the chief object of all eclipse expeditions since the middle 
of the century now drawing to a close, and I believe it is safe 
to say that every one of the short and fleeting opportunities of 
observing the corona with modern instruments and under modern 
conditions which have been afforded by the recurrence of total 
eclipses has been made the most of by an earnest band of 
observers since the famous eclipse of 1842 presented the problem 
as a burning question to the attention of astronomers. The 
introduction of the spectroscope and the possibilities which it 
presented of throwing new light on the subject still further 
increased the interest taken in the observation of the corona 
at the time of total eclipse, this being the only time at which 
such observation is possible. 
It is not my intention now to enquire into what additional 
facts have been gleaned from the observation of successive 
eclipses, but if anyone were to enquire whether the great problem 
has yet been solved, it would be almost sufficient to point, in reply, 
to the ever-increasing number of observers who are attacking 
