gins's spectroscope, May 16, proved to be of a
composition highly significant as to the nature of the catastrophe. The
star--which had already declined below the third magnitude--showed what
was described as a double spectrum. To the dusky flutings of Secchi's
third type four brilliant rays were added.[1467] The chief of these
agreed in position with lines of hydrogen; so that the immediate cause
of the outburst was inferred to have been the eruption, or ignition, of
vast masses of that subtle kind of matter, the universal importance of
which throughout the cosmos is one of the most curious facts revealed by
the spectroscope.

T Coronae (as the new star was called) quickly lost its adventitious
splendour. Nine days after its discovery it was again invisible to the
naked eye. It is now a pale yellow, slightly variable star near the
tenth magnitude, and finds a place as such in Argelander's charts.[1468]
It was thus obscurely known before it made its sudden leap into
notoriety.

The next "temporary," discovered by Dr. Schmidt at Athens, November 24,
1876, could lay no claim to previous recognition even in that modest
rank. It was strictly a parvenu. There was no record of its existence
until it made its appearance as a star of nearly the third magnitude, in
the constellation of the Swan. Its spectrum was examined, December 2, by
Cornu at Paris,[1469] and a few days later by Vogel and O. Lohse at
Potsdam.[1470] It proved of a closely similar character to that of T
Coronae. A range of bright lines, including those of hydrogen, and
probably of helium, stood out from a continuous background impressed
with strong absorption. It may be presumed that in reality the gaseous
substances, which, by their sudden incandescence, had produced the
apparent conflagration, lay comparatively near the surface of the star,
while the screen of cooler materials intercepting large portions of its
light was situated at a considerable elevation in its atmosphere.

The object, meanwhile, steadily faded. By the end of the year it was of
no more than seventh magnitude. After the second week of March, 1877,
strengthening twilight combined with the decline of its radiance to
arrest further observation. It was resumed, September 2, at Dunecht,
with a strange result. Practically the whole of its scanty light (it had
then sunk below the tenth magnitude) was perceived to be gathered into a
single bright line in the green, and that the most characteristic