2 THE BODIES OF SPACE, 



might be assumed in that instance as not less than 19,200,000 

 millions of miles ! In the case of the most brilliant star, 

 Sirius, even this minute parallax could not be found ; from 

 which, of course, it was to be inferred that that star is farther 

 removed than even this vast distance. In some others, on 

 which the experiment has been tried, it was equally impos- 

 sible to detect a parallax. We seemed thus to be left in a 

 hopeless state of ignorance regarding the measurements of the 

 sidereal universe, as if it were such a question as man was not 

 destined ever to answer ; but at length, in our own time, re- 

 sponses came from several points almost at once. By Pro- 

 fessor Henderson, it was ascertained that the star a of the 

 constellation of the Centaur, the third in brightness in our 

 heavens, but in reality a double star, and believed for various 

 reasons to be among those nearest to us, had a parallax of a 

 full second, establishing its distance in miles at about nineteen 

 millions of millions. Afterwards, Bessel assigned a parallax 

 of thirty-one hundredths of a second to the double star 61 

 Cygni, placing it at a distance nearly 670,000 times that of 

 the earth from the sun. 1 Such are but the first steps we take 

 in imagination amongst the hosts of orbs by which we are 

 surrounded. If we suppose that similar intervals exist be- 

 tween all the stars, we shall readily see that the space occupied 

 by even the comparatively small number visible to the naked 

 eye must be vast beyond all powers of human conception. 



The number visible to the eye is about three thousand ; but 

 when a telescope of small power is directed to the heavens, a 

 great number more come into view, and the number is ever 

 increased in proportion to the increased power of the instru- 

 ment. In one place, where they are more thickly sown than 

 elsewhere, Sir William Herschel reckoned that fifty thousand 

 passed over a field of view two degrees in breadth in a single 

 hour. It was first surmised by the ancient philosopher, 

 Democritus, that the faintly white zone which spans the sky 

 under the name of the Milky Way, might be only a dense 

 collection of stars too remote to be distinguished. This 

 conjecture has been verified by the instruments of modern 

 astronomers, and some speculations of a most remarkable kind 

 have been formed in connexion with it. By the joint labours 

 of the two Herschels, the sky has been " gauged" in all direc- 



1 Herschel's Address to Astron. Soc. of London, 1841, and Transac- 

 tions of that body, vol. xii. 



