NEBULJE. 299 



to which the greater number of our astronomers of the present 

 day incline. Like Galileo, Hevel of Dantzig, who, although 

 a distinguished observer, was not much inclined to rely upon 

 telescopic observation for aid in cataloguing the stars," made 

 no mention in his writings of the great nebula in Orion. His 

 star catalogue, moreover, did not contain upwards of 16 

 nebulous spots, of which the positions were accurately 

 determined. 



At length, in the year 1656, Huygens discovered 1 * the 

 nebula in the sword of Orion, which is so important from its 

 extent and form, and has become so famous from the number 

 and celebrity of its subsequent investigators. Huygens was 

 the means of inducing Picard (in 1678) to devote himself 

 diligently to the investigation of this nebulous body. Ed- 

 mund Halley, during his sojourn in St. Helena in 1677, was 

 the first to determine any of the nebulous spots belonging to 

 portions of the southern heavens not visible in Europe, 

 although his observations embraced only a very small number. 

 The lively interest taken by the great Cassini (Jean Dominique) 

 in all branches of contemplative astronomy, led him, towards 

 the close of the seventeenth century, to a more careful explo- 

 ration of the nebula? in Andromeda and Orion. He thought 

 he could detect alterations in the latter since Huygens' ob- 

 servations, and that he " had recognized stars in the former 



13 Compare Cosmos, vol. iii. p. 51. I also remember a 

 vignette at the close of the introduction to Revel's Firma- 

 mentum Sobesciamim, 1687, in which three genii are repre- 

 sented, two of whom are making observations with Hevel's 

 sextants. The third genius is carrying a telescope which 

 he appears to be offering, while those observing, exclaim, 

 Prcestat nudo oculo ! 



14 Huygens, Systema Sahmmnn, in his Opera varia, Lugd. 

 Bat. 1724, torn. ii. pp. 523 and 593. 



