490 COSMOS. 



By the careful application of large telescopes, it has gra- 

 dually become possible to construct a topographical chart of 

 the Moon, based upon actual observations; and since, in the 

 opposition, the entire half-side of the Earth's satellite pre- 

 sents itself at the same moment to our investigation, we 

 know more of the general and merely formal connection of 

 the mountain groups in the Moon, than of the orography 

 of a whole terrestrial hemisphere containing the interiors of 

 Africa and Asia. Generally the darker parts of the disc are 



passage is, at the same time, not without interest for ancient 

 geography. See Humboldt, Examen critique de I' Hist, de la 

 Geogr. torn. i. p. 145. With regard to other views of the 

 -ancients, see Anaxagoras and Democritus, in Plut. de plac. 

 Philos. ii. 25; Paruienides, in Stob. pp. 419, 453, 516, and 

 563, ed. Heeren; Schneider, Ecloya physicce, vol. i. pp. 433- 

 443. According to a very remarkable passage in Plutarch's 

 Life of Nicias, cap. 42, Anaxagoras himself, who calls "the 

 mountainous Moon another Earth," had made a drawing of 

 the Moon's disc. (Compare also Origines, Philosophumena, 

 cap. 8, ed. Mulleri, 1851, p. 14.) I was once very much 

 astonished to hear a very well-educated Persian, from Ispahan, 

 who certainly had never read a Greek book, mention, when I 

 showed him the Moon's spots in a large telescope in Paris, 

 the hypothesis of Agesinax, (alluded to in the text,) as to the 

 reflection, as a widely-diffused popular belief in his country. 

 "What we see there in the Moon," said the Persian, 4t is 

 ourselves; it is the map of our Earth." One of the interlo~ 

 cutors in Plutarch's Moon-dialogue, would not have expressed 

 himself otherwise. If it can be supposed that men are inha- 

 bitants of the Moon, destitute of water and air, the Earth, 

 with its spots, would also present to them such a map upon a 

 nearly black sky by day. with a surface fourteen times greater 

 than that which the full Moon presents to us, and always in 

 the same position. But the constantly varying clouds and 

 obscurities of our atmosphere, would confuse the outlines of 

 the continents. Compare Madler's Astron. p. 169, and Sir 

 John Herschel, Outlines, 436. 



