orbits, the eccentricity being 0⋅41; Tempel's First Periodical Comet comes next with an eccentricity of 0⋅46.
Fig. 38, Plate XI. is a representation of Holmes's Comet in the same field as the Great Nebula in Andromedæ (31 M.), enlarged from a photograph taken by E. E. Barnard on Nov. 10, 1892.
(11.) Brooks's Second Periodical Comet (1889, v.).
The comet discovered by Brooks on July 6, 1889, is interesting both in itself and as regards its orbit. When first seen it was rather faint and had a short wide tail, and did not undergo any great change of appearance during the remainder of the month, but on Aug. 1 it was found to have thrown off fragments 4 in number. Two of these were very faint and soon disappeared, but the other 2 brighter ones were miniatures of the main body, each having a nucleus and a tail. For a while they moved away from their primary. In 3 weeks the nearer companion ceased to recede; it then expanded, and finally disappeared. The farther companion continued to recede until it had become (a month from discovery) brighter than the parent comet. In another month it began to approach its parent; its head swelling and becoming faint, the tail disappearing. Altogether, the history of these transformations is very curious.[1] The small inclination and direct motion noticed when its orbit was determined suggested that the comet was a periodical one, and this fact was soon established. The orbit at aphelion approaches very closely to that of Jupiter, and Chandler found that in 1886 the comet's distance from the planet did not exceed 110th of the Earth's mean distance from the Sun, from which fact it has been assumed that the comet's orbit acquired its present ellipticity then and on that account: and that Jupiter or Jupiter's Satellites had had some share in fracturing the comet as above described.
This comet returned in 1896, and was found by Javelle at Nice on June 20, as a single comet, no companions or frag-
- ↑ Ast. Nach., vol. cxxii, No. 2919, Aug. 29, 1889; Ibid., No. 2922, Sept. 6, 1889.
