llV NOTES. 



figures, " Andromeda must lay her arm in another place than that which it 

 has occupied for 3000 years." 



( 198 ) p. 105. Kosmos, Bd. iii. S. 37 and 53 (English edition, p. 28 and 

 note 52). 



('") p. 105. According to Democritus and his scholar Metrodorus, Stob 

 Eclog. phys. p. 582. 



( 20 ) p. 106. Plut. de Plac. Phil. ii. 11 ; Diog. Laert. viii. 77 ; Achilles. 

 Tat. ad Arat. cap. 5 ; Efjnr, /epvoraXXwdj; TOVTOV (TOV ovpavov) tival 

 (ftrjaiv, kit TOV 7rayra>ou <rv\\fysvra ; so also we find only the expression 

 crystal-like or crystalline in Diog. Laert. viii. 77, and Galenus, Hist. phil. 12 

 (Sturz*, Empedocles Agrigent, T. i. p. 321). Lactantius de opificio Dei, c. 

 17 : an si mini quispiam dixerit ceneum esse coelum, aut vitreum, aut, ut 

 Empedocles ait, serem glaciatum, statimne assentiar, quia coelum ex qua ma- 

 teria sit ignorem? Respecting this cffilum vitreum, we have no earlier Hel- 

 lenic evidence ; for only one celestial body, the Sun, is termed by Philolaos a 

 glass-like or vitreous body, which receives and throws back to us the rays 

 from the central fire. The view of Empedocles, referred to in the text, of the 

 reflection of the solar light from the Moon, speaking of the latter as a body 

 which had consolidated in the manner of hail stones, is mentioned by Plu- 

 tarch, apud Euseb. Praep. Evangel, i. p. 21, D, and de facie in orbe Lunse, 

 cap. 5. When in Homer and Pindar the epithets xaXjeeog and ffiSnpeog are 

 applied to Uranos, it is only in a figurative sense, like hearts of brass, voice 

 of brass, as signifying stedfast, enduring, imperishable (Volcker u'ber Home- 

 rische Geographic, 1830, S. 5). The word icpvcrraXXog applied to the ice- 

 like, transparent substance of rock-crystal, first occurs before Pliny, in Dyo- 

 nisius Periegetes, 781, JElian, xv. 8, and in Strabo, xv. p. 717, Casaub. 

 The supposition that the idea of the crystal heavens, as a vault of ice (aer 

 glaciatus of Lactantius), had arisen among the ancients, from observing, when, 

 travelling among mountains, the increasing cold in ascending, and from the 

 sight of snow-capped mountains, is refuted by our knowing that they imagined 

 a fiery ether to exist at the limit of our atmosphere (Aristot. Meteorol. i. 3 ; 

 de Caelo, ii. 7, p. 289). In speaking of the music of the spheres, which, 

 " according to the Pythagoreans, is unheard by men because it never ceases, 

 and sounds are only heard if interrupted by silence," Aristotle (de Coelo, ii. 

 p. 290) affirms, singularly enough, that the motion of the spheres produces 

 heat in the air below, but without heating themselves. Their vibrations pro- 

 duce heat, not sound. " The motion of the sphere of the fixed stars is the 

 most rapid (Aristot. de Cselo, ii. 10, p. 291) j and while this sphere and the 



