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POPULAR SCIENCE REVIEW. 
The effect of the corrections on the choice of stations would he very small. 
The central line would be shifted nearly five miles farther south, and the 
breadth of the shadow increased by about double that amount, whilst the 
time of first contact would be accelerated and of last contact retarded by 
about 10s. 
These last results may seem to be now unimportant ; but it is well to 
notice how the observation of eclipses is preparing the way for increased 
accuracy, both as respects the prediction of future eclipses, and that analysis 
of the features of past eclipses which has already thrown so important a 
light not merely on astronomical questions but on historical events. 
The Solar Corona . — Since our last summary appeared, more facts have 
come to light respecting the solar corona, as seen during the last eclipse, 
and there has been a good deal of discussion over the significance of the 
new facts brought to our knowledge. On nearly all sides the atmospheric 
glare theory of the corona has now been abandoned, though the repeated 
statement of this fact by various writers in the correspondence-columns of 
a contemporary weekly science-paper has given rise to as repeated editorial 
denials (the editor being the chief, we had almost said the only remaining, 
advocate of the glare theory in this country). But although the solar 
nature of the corona is now generally admitted, we are very far indeed from 
having solved the problems of difficulty presented by solar phenomena. 
Indeed we may.be said to have barely entered upon this difficult field of 
research. 
Various ideas which had been broached respecting the corona can now be 
discussed under somewhat more satisfactory circumstances than before the 
late eclipse. Two papers have appeared during the last two months which 
bear on the theoretical considerations suggested by the observations made 
last December. In one Mr. Proctor points to the significance of the observed 
connection between the corona, the prominences, and the solar spot regions ; 
and he points out that, judging from the evidence now in our hands, the 
theory seems suggested that all the phenomena — corona, prominences, and 
sun-spots — are dependent “on the action of vertical forces, or, at any rate, of 
forces directed outwards from the Sun’s globe — though not necessarily exactly 
radial.” Abandoning the meteoric theory of the corona, or rather speaking 
of it as insufficient to account for the observed phenomena, he considers the 
probable effects of eruptive or repulsive forces exerted by the Sun on matter 
in the first place within his visible globe, and he shows that many somewhat 
perplexing phenomena seem to receive an interpretation when this theory is 
(provisionally) adopted. In the other paper, Professor Young, of America, 
after pointing out some objections to the meteoric theory of the corona, 
remarks that the low specific gravity of the coronal matter may depend on 
the action of u such solar repulsion as appears to be operative in the forma- 
tion of a comet’s tail.” In this paper he points out very lucidly how small 
the influence must be which our atmosphere is capable of exerting in in- 
creasing the seeming importance of the corona. u Some influence our atmo- 
sphere must, of course, have ; but remembering how much the inner portion 
of the coronal ring exceeds in brilliance the outer, it would seem that the 
illumination of the lunar disc must give us an exaggerated measure of the 
true atmospheric effect. This illumination makes the edge of the Moon 
