15,000,000 miles. This comet is undoubtedly a periodical one. Argelander, whose investigation of the orbit is the most complete, assigned to it a period of 3065 years, subject to an uncertainty of only 43 years.[1] The aphelion distance is 14 times that of Neptune, or, say, 40,000,000,000 miles.
The comet of 1811 obtained in Western Europe, and especially in Great Britain, fame of a very un-astronomical character. Its year of appearance was also the year of an unusually celebrated port wine vintage in Portugal, and "Comet Wine" figured for a long period of years, first of all in the price-lists of wine merchants, and afterwards in the cellar books of many private houses, and finally in the advertisements of auction sales. The last such advertisement which I remember to have seen appeared in the Times somewhere in the "Eighties", so the wine and the label thereof lasted long.
The Comet of 1843 (i.) was another very celebrated comet, and I once came upon the following remarks made by one who had seen Donati's Comet of 1858, as well as that of 1843, and was able to compare the one with the other. General J. A. Ewart wrote thus of the comet of 1843:—
"It was during our passage from the Cape of Good Hope to the Equator, and when not far from St. Helena, that we first came in sight of the great comet of 1843. In the first instance a small portion of the tail only was visible, at right angles to the horizon; but night after night as we sailed along, it gradually became larger and larger, till at last up came the head, or nucleus, as I ought properly to call it. It was a grand and wonderful sight, for the comet now extended the extraordinary distance of one-third of the heavens, the nucleus being, perhaps, about the size of the planet Venus."[2]
General Ewart thus speaks of Donati's Comet of 1858, which will be described on a later page:—
"A very large comet made its appearance about this time, and continued for several weeks to be a magnificent object at night; it was, however, nothing to the one I had seen in the year 1843, when on the other side of the Equator."
Writing from the Cape of Good Hope on Nov. 12, 1843,
