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tempting a general analysis of the work. We may, however, dwell on some 
of its more novel and interesting features. These, it appears to us, are to 
be found in the chapter entitled, l( What we learn from the Sun.” In 
this section of his work, which is essentially controversial, the author enters 
upon a discussion of the several moot points in connection with the late 
solar observations. In reference to the sun’s corona and the zodiacal light, 
subjects which readers will be aware have of late received considerable atten- 
tion, Mr. Proctor has much to say. He enters with considerable minuteness 
into the consideration of Mr. Lockyer’s hypothesis on the origin of the sun’s 
corona, and he adduces certain very formidable arguments against these views 
and in favour of his own opinions. It would be impossible to put the author’s 
observations into a smaller compass than he has himself compressed them, 
and as they occupy several pages we could not possibly reproduce them in 
full. We, however, may just quote one passage, which, to a certain extent, 
contains the pith of Mr. Proctor’s ideas on the point in question. After 
commenting on the spectroscopic evidence as to the corona and on the “ at- 
mospheric glare” theory of Mr. Lockyer, he goes on to say : — 
“ Now, remembering that we have two established facts for our guidance 
— (1) the fact that the corona cannot be a solar atmosphere, and (2) the 
fact that it must be a solar appendage — I think a way may be found towards 
a satisfactory explanation. Let it be premised that the bright lines of the 
coronal spectrum correspond in position to those seen in the spectrum of the 
Aurora, and that the same lines are seen in the spectrum of the zodiacal 
light, and in that of the phosphorescent light occasionally seen over the 
heavens at night. Since we have every reason to believe that the light of 
the aurora is due to electrical discharges taking place in the upper regions 
of the air, we are invited to the belief that the coronal light may be due to 
similar discharges taking place between the particles (of whatever nature) 
constituting the corona. Now, though the appearance of an aurora is due 
to some special terrestrial action (however excited), yet the material sub- 
stances between which the discharges take place must be assumed to be at 
all times present in the upper regions of air. In all probability they are the 
particles of those meteors which the earth is continually encountering. And 
since we know that meteor-systems must be aggregated in far greater num- 
bers near the sun than near the earth, we may regard the coronal light as 
due to electrical discharges excited by the sun’s action, and taking place be- 
tween the members of such systems. Besides this light, however, there must 
necessarily be a large proportion of light reflected from these meteoric bodies. 
In this way the peculiar character of the coronal spectrum maybe readily 
accounted for. We know from the auroral spectrum that the principal bright 
lines due to the electrical discharges would be precisely where we see bright 
lines in the coronal spectrum. But besides these there would be fainter 
bright lines corresponding to the various elements which exist in the 
meteoric masses. These elements we know are the same as those in the 
substance of the sun. Thus the bright lines would correspond in position 
with the dnrk lines of the solar spectrum. Hence, as light reflected by the 
meteors would give the ordinary solar spectrum, there would result from the 
combination a continuous spectrum on which the bright lines first men- 
tioned would be seen, as during the American eclipse.” 
