Page:Popular Science Monthly Volume 22.djvu/305

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west, and when, once in a while, a clear morning permitted the view, it was seen to be growing fainter and more diffuse, though not smaller.

To the naked eye or opera-glass it has perhaps presented fewer phenomena of interest than some other comets—that of 1858, for instance; it has not exhibited any of the peculiar secondary tails or straight streamers which were so characteristic of that comet, nor has the striation of the tail been marked, though evident enough on close inspection.

From September 27th to October 1st, however, the tail was "rifted." There was one obscure streak extending from the nucleus through its whole length, described both by Ricco, of Palermo, and Dr. Hastings, of Baltimore, and the latter mentions another fainter one parallel to the first, and shorter. On October 2d the tail, as seen at Princeton, was about 14° long, exceedingly bright and sharp in its outlines, slightly curved and convex to the horizon. It was especially well defined near the head, and almost equally so on both sides. On the 4th the upper edge was veiled and rendered indefinite by a faint nebulosity which appeared to have emanated from the head. Ricco's drawing of it, as seen at this date in the clear Italian sky, shows something resembling a bright comet, enveloped in a fainter one; but the smaller one is eccentric, and south of the middle of the hazy envelope.

On the 10th this external nebulosity had considerably increased. Professor Smith, of Kansas University, noticed on the 9th a pale stream of light with parallel edges, and nearly as wide as the tail of the comet, extending toward the sun. On the 15th the phenomenon had become much more conspicuous. The streamer was now over PSM V22 D305 The great comet of 1882 on october 15.jpgFig. 1.—October 15, 1882. half a degree in width, well defined at both edges, of nearly uniform brightness throughout, though nowhere as bright as even the faintest portions of the tail, and extended from its origin, a degree or two above the nucleus, to a distance of two or three decrees below the head, where it faded out. The dotted lines in Fig. 1 indicate its form and dimensions.

This streamer, which remained visible only a few days, may have originated in the enveloping comet of Ricco's figure just spoken of, but no other comet is known to have shown anything of the kind. It is not to be confounded with the sunward jets sometimes ejected by cometary nuclei, nor did it at all resemble the anomalous tail, directed toward the sun, shown by Pechüle's comet (in December, 1880), in addition to its ordinary tail.