56 Things not generally Known. 



the geometrical consideration of the five regular bodies, to the 

 musical intervals of tone which determine a word and form 

 different kinds of sounds, extended it even to the system of 

 the universe itself; supposing that the moving, and, as it were, 

 vibrating planets, exciting sound-waves, must produce a spheral 

 music, according to the harmonic relations of their intervals of 

 space. " This music," they add, " would be perceived by the 

 human ear, if it was not rendered insensible by extreme famili- 

 arity, as it is perpetual, and men are accustomed to it from 

 childhood." 



The Pythagoreans affirm, in order to justify the reality of the tones 



ng take 

 where there is an alternation of sound and silence. The inaudibility of 



, 

 produced by the revolution of the spheres, that hearing takes place only 



the spheral music is also accounted for by its overpowering the senses. 

 Aristotle himself calls the Pythagorean tone-myth pleasing and ingeni- 

 ous, but untrue. 



Plato attempted to illustrate the tones of the universe in an 

 agreeable picture, by attributing to each of the planetary spheres 

 a syren, who, supported by the stern daughters of Necessity, 

 the three Fates, maintain the eternal revolution of the world's 

 axis. Mention is constantly made of the harmony of the 

 spheres, though generally reproachfully, throughout the writ- 

 ings of Christian antiquity and the Middle Ages, from Basil the 

 Great to Thomas Aquinas and Petrus Alliacus. 



At the close of the sixteenth century, Kepler revived these 

 musical ideas, and sought to trace out the analogies between 

 the relations of tone and the distances of the planets ; and Tycho 

 Brahe was of opinion that the revolving conical bodies were 

 capable of vibrating the celestial air (what we now call "resist- 

 ing medium") so as to produce tones. Yet Kepler, although he 

 had talked of Venus and the Earth sounding sharp in aphelion 

 and flat in perihelion, and the highest tone of Jupiter and that 

 of Venus coinciding in flat accord, positively declared there 

 to be " no such things as sounds among the heavenly bodies, 

 nor is their motion eo turbulent as to elicit noise from the attri- 

 tion of the celestial air." (See Things not generally Knoivn^. 44.) 



" MORE WORLDS THAN ONE." 



Although this opinion was maintained incidentally by va- 

 rious writers both on astronomy * and natural religion, yet M. 



* The original idea is even attributed to Copernicus. M. Blundevile, in his 

 Treatise on Cosmogrnphy , 1594, has the following passage, perhaps the most dis- 

 tinct recognition of authority in our language: " How prooue (prove) you that 

 there is but one world ? By the authentic of Aristotle, who saieth that if there 

 were any other world out of this, then the earth of that world would mooue 

 (move) towards the centre of this world," &c. 



Sir Isaac Newton, in a conversation with Conduitt, said he took "all the 

 planets to be composed of the same matter with the earth, viz. earth, water, aud 

 stone, but variously concocted." 



