THE ISSUES OF THE LATE ECLIPSE. 
139 
time before the appearance of the actual limb of tbe sun, and 
at sunset be would see the corona linger after the sinking of 
the solar disc. The lunar surface must at sunrise and sunset 
be illuminated by a coronal twilight , which will be of consider- 
able duration on account of the moon’s slow rotation. It is 
therefore possible that if the faint light seen upon the moon’s 
terminator (the boundary zone of light and darkness) were 
analysed by the spectroscope it would reveal the coronal lines. 
At all events, the experiment would be worth trying, and there 
are abundant opportunities for it. The position of the “1474” 
line, with respect to lines of known substances, may thus be 
deliberately determined, and some more reliable evidence ob- 
tained to aid a judgment whether it belongs to a new element 
— as Professor Young has suggested, some occluded gas, perhaps 
standing in relation to the magnetic powers of iron of whose 
spectrum the line is apparently a part — or whether it may be 
due to iron in any uncommon form or condition. 
Reverting to the immediate results of the late eclipse, we 
remark that a faint continuous spectrum of the corona, without 
visible dark lines, was noted by several observers, among whom 
were Lieutenant Brown, Captain Maclear, and Professor Win- 
lock, and that a highly interesting observation, not relating to 
the corona, however, was made by Professor Young. At the 
commencement of the totality he saw for an instant the whole 
of the Fraunhofer lines of the solar spectrum reversed, and the 
field of his spectroscope filled with bright lines. He must 
then have caught a glimpse of the stratum of burning elements 
that lays immediately above the photosphere — an observation 
made once, and once only, by Lockyer, without an eclipse. 
The polariscopic observations confirm those with the spectro- 
scope which indicate that a part of the coronal light is reflected, 
though they leave open the question whether that reflection 
occurs in or beyond our atmosphere. Professors Pickering and 
Langley are reported to have found that a considerable propor- 
tion of the light is polarised, and in a radial direction ; the 
first-named observer obtaining the same results with three 
forms of polariscope. Professor Blaserna, observing in Sicily, 
asserts that the corona was strongly polarised, the only doubt 
with him being as to whether the plane was radial to the sun 
or tangential. Mr. Ranyard, at Villamonda, made three ob- 
servations, two of which showed what was expected to be 
observed in the case of radial polarisation. Mr. Pierce, jun., 
arrived at a similar result, and so did Mr. Ladd. Mr. Samuel- 
son, observing not upon the corona but upon the sky, first, far 
on one side of the sun, and then far below it, found vertical 
polarisation. 
It would be difficult at the present time to define the precise 
