[ [2] The Observatory, No. 43, p. 613.
[ [3] Nature, vol. xxv. p. 537.
[ [4] Silvered glass is considerably more reflective than speculum-metal, and Mr. Common’s 36-inch mirror can be but slightly inferior in luminous capacity to the Lick objective. It is, however, devoted almost exclusively to celestial photography, in which it has done splendid service. The Paris 4-foot mirror bent under its own weight when placed in the tube in 1875, and has not since been remounted.
[ [5] E. Holden, “The Lick Observatory,” Nature, vol. xxv. p. 298.
[ [6] Monthly Notices, R. Astr. Soc. vol. xiv. p. 133 (1854).
[ [7] Phil. Trans. vol. cxlviii. p. 455.
[ [8] Captain Jacob unfortunately died August 16, 1862, when about to assume the direction of a hill observatory at Poonah.
[ [9] The height of the mercury at Guajara is 21·7 to 22 inches.
[ [10] Phil. Trans. vol. cxlviii. p. 477.
[ [11] We are told that three American observers in the Rocky Mountains, belonging to the Eclipse Expedition of 1878, easily saw Jupiter’s satellites night after night with the naked eye. That their discernment is possible, even under comparatively disadvantageous circumstances is rendered certain by the well-authenticated instance (related by Humboldt, “Cosmos,” vol. iii. p. 66, Otte’s trans.) of a tailor named Schön, who died at Breslau in 1837. This man habitually perceived the first and third, but never could see the second or fourth Jovian moons.