strong resemblance to the bright line spectrum
of the chromosphere of the sun became very evident. The hydrogen lines
were very conspicuous, while the iron lines were very numerous, and
calcium and magnesium were also represented. The most remarkable
revelation made by the photographs was, however, that the bright lines
were in many cases accompanied, on the side next the violet, by broad
dark bands, while both bright and dark lines were of a composite
character. Many of the dark lines had a thin bright line superposed in
the middle, while on the other hand many of the bright lines had two or
three points maxima of brightness. The results of the measures of motion
in the line of sight were of special importance. They showed that the
source of light, whence came the thin bright lines within the dark ones,
was travelling towards the sun at the enormous rate of 400 miles per
second, and if the bright lines were actual "reversals" of the dark
ones, then the source of the absorption spectrum must have been endowed
with much the same velocity. On the other hand, if the two or three
maxima of brightness in the bright lines really represent two or three
separate bodies giving bright lines, the measures indicate that the
principal one was almost at rest as regards the sun, while the others
were receding from us at the extraordinary rates of 300 and 600 miles
per second. And as if this were not sufficiently puzzling, the star on
its revival in August, 1892, as a tenth magnitude star had a totally
different spectrum, showing nothing but a number of the bright lines
belonging to planetary nebulae! It is possible that the principal ones of
these were really present in the spectrum from the first, but that their
wave lengths had been different owing to change of the motion in the
line of sight, so that the nebula lines seen in the autumn were
identical with others seen in the spring at slightly different places.
Subsequent observations of these nebula lines seemed to point to a
motion of the Nova towards the solar system (of about 150 miles per
second) which gradually diminished.

But although we are obliged to confess our inability to say for certain
why a temporary star blazes up so suddenly, we have every cause to think
that these strange bodies will by degrees tell us a great deal about the
constitution of the fixed stars. The great variety of spectra which we
see in the starry universe, nebula spectra with bright lines, stellar