e of 10 deg. This was easily shown by
Bredikhine to belong to the hydrogen type of tails;[1305] while a
"strange, faint second tail, or bifurcation of the first one," observed
by Captain Noble, August 24,[1306] fell into the hydro-carbon class of
emanations. It was seen, August 22 and 24, by Dr. F. Terby of
Louvain,[1307] as a short nebulous brush, like the abortive beginning of
a congeries of curving trains; but appeared no more. Its well-attested
presence was significant of the complex constitution of such bodies, and
the manifold kinds of action progressing in them.

The only peculiarity in the spectrum of Schaeberle's comet consisted in
the almost total absence of continuous light. The carbon-bands were
nearly isolated and very bright. Barely from the nucleus proceeded a
rainbow-tinted streak, indicative of solid or liquid matter, which, in
this comet, must have been of very scanty amount. Its visit to the sun
in 1881 was, so far as is known, the first. The elements of its orbit
showed no resemblance to those of any previous comet, nor any marked
signs of periodicity. So that, although it may be considered probable,
we do not _know_ that it is moving in a closed curve, or will ever again
penetrate the precincts of the solar system. It was last seen from the
southern hemisphere, October 19, 1881.

The third of a quartette of lucid comets visible within sixteen months,
was discovered by Mr. C. S. Wells at the Dudley Observatory, Albany,
March 17, 1882. Two days later it was described by Mr. Lewis Boss as "a
great comet in miniature," so well defined and regularly developed were
its various parts and appendages. Discernible with optical aid early in
May, it was on June 5 observed on the meridian at Albany just before
noon--an astronomical event of extreme rarity. Comet Wells, however,
never became an object so conspicuous as to attract general attention,
owing to its immersion in the evening twilight of our northern June.

But the study of its spectrum revealed new facts of the utmost interest.
All the comets till then examined had been found (with the two
transiently observed exceptions already mentioned) to conform to one
invariable type of luminous emission. Individual distinctions there had
been, but no specific differences. Now all these bodies had kept at a
respectful distance from the sun; for of the great comet of 1880 no
spectroscopic inquiries had been made. Comet Wells, on the other hand,
approached its su