Curiosities of Science. 75 



in the heavens by that luminary. On these occasions is ex- 

 hibited the most striking and impressive of all the occasional 

 phenomena of astronomy, an Eclipse of the Sun, in which a 

 greater or less portion, or even in some conjunctures the whole 

 of its disc, is obscured, and, as it were, obliterated, by the su* 

 perposition of that of the moon, which appears upon it as a 

 circularly-terminated black spot, producing a temporary dimi- 

 nution of daylight, or even nocturnal darkness, so that the 

 stars appear as if at midnight. Sir John Herschel's Outlines. 



VAST NUMBERS IN THE UNIVERSE. 



The number of telescopic stars in the Milky Way uninter- 

 rupted by any nebulae is estimated at 18,000,000. To com- 

 pare this number with something analogous, Humboldt calls 

 attention to the fact, that there are not in the whole heavens 

 more than about 8000 stars, between the first and the sixth 

 magnitudes, visible to the naked eye. The barren astonish- 

 ment excited by numbers and dimensions in space when not 

 considered with reference to applications engaging the mental 

 and perceptive powers of man, is awakened in both extremes 

 of the universe in the celestial bodies as in the minutest 

 animalcules. A cubic inch of the polishing slate of Bilin con- 

 tains, according to Ehrenberg, 40,000 millions of the siliceous 

 shells of Galionellse. 



FOR WHAT PURPOSE WERE THE STARS CREATED 1 



Surely not (says Sir John Herschel) to illuminate our nights, 

 which an additional moon of the thousandth part of the size of 

 our own would do much better ; nor to sparkle as a pageant 

 void of meaning and reality, and bewilder us among vain con- 

 jectures. Useful, it is true, they are to man as points of exact 

 and permanent reference ; but he must have studied astronomy 

 to little purpose, who can suppose man to be the only object of 

 his Creator's care, or who does not see in the vast and wonder- 

 ful apparatus around us provision for other races of animated 

 beings. The planets derive their light from the sun ; but that 

 cannot be the case with the stars. These doubtless, then, are 

 themselves suns ; and may perhaps, each in its sphere, be the 

 presiding centre round which other planets, or bodies of which 

 we can form no conception from any analogy offered by our 

 own system, are circulating.* 



NUMBER OF STARS. 



Various estimates have been hazarded on the Number of 

 Stars throughout the whole heavens visible to us by the aid of 



* This eloquent advocacy of the doctrine of " More Worlds than One" (refer- 

 red to at p. 51) is from the author's valuable Outlines of Astronomy. 



