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besides the u 1474-matter ” * there is hydrogen in the sun’s atmosphere to 
this height, that is to a distance of upwards of 210,000 miles from the sun. 
Mr. Lockyer endeavoured to see these images of the corona by another plan, 
suggested by Professor Young early in 1871 — the use, namely, of a train of 
prisms without any slit ; but though he saw four images of the circle of 
prominences, the images of the inner corona, as seen by him, extended 
from the sun to only about one-third of the distance observed by Professor 
Respighi, so that it would appear as though the atmospheric conditions had 
not been so favourable in Mr. Lockyer’s case. Mr. Halliday has succeeded 
in obtaining excellent drawings of the corona. The observing party from 
the observatory at Madras, under Mr. Pogson, the government astronomer 
there, did excellent work at Avenashy, obtaining good photographs, and 
confirming many of the spectroscopic observations made during former eclipses. 
Col. Tennant’s party, at Dodabetta, also obtained six good photographs. 
Among the spectroscopic observations made by this party must be noted the 
complete confirmation of Professor Young’s important discovery that the 
Fraunhofer lines undergo reversal at the moment when totality is complete. 
It is now demonstrated that the region where the absorption takes place to 
which the Fraunhofer lines are due, is an atmosphere of great complexity, 
relatively very shallow, and under ordinary circumstances either wholly un- 
recognisable by the spectroscopist, or only to be recognised by its effect in 
causing the spectrum of the very edge of the sun’s limb tp appear continuous. 
M. Janssen, who was to have gone to Java, preferred, on inquiring into 
meteorological relations, to take up his station at Ootacamund, on the 
Neilgherries. Here, with a telescope of larger aperture than had yet been 
applied to the spectroscopic analysis of the corona, and raised higher above 
the sea-level than any former observer of the eclipsed sun, he made obser- 
vations of the utmost interest and importance. His general conclusions 
respecting the corona are indicated in the following words addressed by him 
to the secretary and president of the Paris Academy of Sciences. “ Nothing 
could be more beautiful, more luminous, than the corona ; with special 
forms excluding all possibility of a terrestrial atmospheric origin. I think 
the question whether the corona is due to the terrestial atmosphere is 
disposed of (tranchee) ; and we have before us the study of the extra solar 
regions, which will be very interesting and fruitful.” . . . “ The spectrum 
of the corona, which contains a very remarkable bright green line already 
announced, is not continuous as has been asserted, and I have found in- 
dications of the dark lines of the solar spectrum, notably D.” The re- 
cognition of the solar dark lines in the coronal spectrum is a circumstance 
of extreme importance, as demonstrating the fact, hitherto only suspected, 
that a proportion of the coronal light is simply reflected sunlight. 
Spectrum of the Zodiacal Light. — M. Liais, at Rio Janeiro, has succeeded 
in observing the spectrum of the zodiacal light. It will be remembered 
that the eminent Swedish spectroscopist, Angstrom, had announced that 
the zodiacal light is monochromatic, its spectrum being the same yellow- 
green light which appears in the spectrum of the aurora borealis. It would 
appear that Angstrom was misled by real auroral light, not recognisable 
* The name suggested by Professor Young for the substance producing 
the line corresponding to division 1474 of Kirchhoff’s scale. 
