NOTES. CXV11 



Rigaud, pp. 32 and 38. The Jesuit Schoner, who was summoned from Gratz 

 to Rome, has been accused of seeking to revenge himself of Galileo on account 

 of the literary contest respecting the discovery of the solar spots, by getting it 

 whispered, through another Jesuit, Grassi, to Pope Urban VIII. that he (the 

 Pope) was the person represented by the foolish and ignorant Simplicius in the 

 Dialoghi delle Scienze Nuove (Nelli, Vol. ii. p. 515). 



( 49 ) p. 320. Delambre, Hist, de 1'Astronomie moderne, T. i. p. 690. 



( 49 ) p. 320. In Galileo's Letters to the Principe Cesi (May 25, 1612) the 

 same opinion is expressed ; Venturi, P. i. p. 172. 



( 492 ) p. 321. See on this subject some ingenious and interesting conside- 

 rations by Arago, in the Annuaire pour 1'an 1842, pp. 481488. (The 

 experiments with Drummond's light projected on the sun's disk are mentioned 

 by Sir John Herschel in his Astronomy, S. 334.) 



( 493 ) p. 321. Giordano Brano und Nic. von Cusa verglichen, von 

 J. Clemens, 1847, S. 101. On the phases of Venus, see Galileo, Opere, T. ii. 

 p. 53, and Nelli, Vita, Vol. i. pp. 213215. 



( 494 ) p. 322. Compare Kosmos, Bd. i. S. 160 and 416 ; Eng. translation, 

 Vol. i. p. 144, Note 120. 



( 495 ) p. 323. Laplace says of Kepler's theory of the measurement of casks 

 (Stereometria doliorum, 1615, which, like Archimedes, contains the develop- 

 ment of elevated ideas in reference to an insignificant subject) : Kepler 

 presente dans cet ouvrage des vues sur 1'infini qui ont influe sur la revolution 

 que la geometric a eprouvee a la fin du 17 me siecle; et Fermat, que Ton doit 

 regarder comme le veritable inventeur du calcul differentiel, a fonde sur elles 

 sa belle methode de maximis et minimis (Precis de 1'hist. de 1'Astronomie, 

 1831, p. 95). On the geometrical acuteness manifested by Kepler in the five 

 books of his Harmonices Mundi, see Chasles, Apercu hist, des Methodes en 

 Geometric, 1837, pp. 482487. 



( 496 ) p. 323. Sir David Brewster says well in the account of Kepler's 

 method of investigating truth : " The influence of imagination as an instru- 

 ment of research has been much overlooked by those who have ventured to 

 give laws to philosophy. This faculty is of greatest value in physical inquiries : 

 if we use it as a guide, and confide in its indications, it will infallibly deceive 

 us ; but if we employ it as an auxiliary, it will afford us the most invaluable 

 aid" (Martyrs of Science, p. 215). 



( 497 ) p. 324. Arago, in the Annuaire, 1842, p. 434 (De la transformation 

 des Nebuleuses et de la matiere diffuse en etoiles). Compare Kosmos, Bd. i. 

 S. 148 and 158 (English translation, Vol. i. pp. 132 and 142). 



