eipt of this letter, he stated that he
had not the 'slightest hesitation' in regarding Mr. Barker's earlier
observations as 'not entitled to the slightest credit.'[33]

It may be fairly taken for granted that the new star leapt very quickly,
if not quite suddenly, to its full splendour. Birmingham, as we have
seen, was the first to notice it, on May 12. On the evening of May 13,
Schmidt of Athens discovered it independently, and a few hours later it
was noticed by a French engineer named Courbebaisse. Afterwards,
Baxendell of Manchester, and others independently saw the star. Schmidt,
examining Argelander's charts of 324,000 stars (charts which I have had
the pleasure of mapping in a single sheet), found that the star was not
a new one, but had been set down by Argelander as between the ninth and
tenth magnitudes. Referring to Argelander's list, we find that the star
had been twice observed--viz., on May 18, 1855, and on March 31, 1856.

Birmingham wrote at once to Mr. Huggins, who, in conjunction with the
late Dr. Miller, had been for some time engaged in observing stars and
other celestial objects with the spectroscope. These two observers at
once directed their telescope armed with spectroscopic adjuncts--the
telespectroscope is the pleasing name of the compound instrument--to the
new-comer. The result was rather startling. It may be well, however,
before describing it, to indicate in a few words the meaning of various
kinds of spectroscopic evidence.

The light of the sun, sifted out by the spectroscope, shows all the
colours but not all the tints of the rainbow. It is spread out into a
large rainbow-tinted streak, but at various places (a few thousand)
along the streak there are missing tints; so that in fact the streak is
crossed by a multitude of dark lines. We know that these lines are due
to the absorptive action of vapours existing in the atmosphere of the
sun, and from the position of the lines we can tell what the vapours
are. Thus, hydrogen by its absorptive action produces four of the bright
lines. The vapour of iron is there, the vapour of sodium, magnesium, and
so on. Again, we know that these same vapours, which, by their
absorptive action, cut off rays of certain tints, emit light of just
those tints. In fact, if the glowing mass of the sun could be suddenly
extinguished, leaving his atmosphere in its present intensely heated
condition, the light of the faint sun which would thus be left us would
giv