THE HERSCHELS AND THE STAR-DEPTHS. 1 5 



every one of these methods must be regarded as in 

 many respects unsatisfactory. We may consider, on 

 the one hand, the seeming minuteness of the distance 

 separating the stars of a nebula from each other, and 

 then endeavour to realize the fact that that distance, 

 only just rendered appreciable by the magnifying 

 power of the largest telescopes man can construct, is 

 assuredly not less but probably exceeds many hundred- 

 fold the distance separating our sun from the neigh- 

 bouring suns this last distance being so enormous 

 that it has been calculated that the swiftly-travelling 

 comets which visit us from the interstellar spaces 

 cannot have occupied less than ten millions of years in 

 traversing it. Or again, we may endeavour to picture 

 to ourselves the vastness of the distances which must 

 separate us from these outlying Milky Ways, when 

 millions of such orbs as our own sun, though all 

 shining at the same time within the field of view of a 

 powerful telescope, yet present only the appearance of 

 a faint milky light which the thinnest haze can blot 

 from our view. Or lastly, and this, perhaps, affords 

 the most striking means of indicating the grandeur of 

 Herschel's conceptions, we may endeavour to picture 

 the fact that this earth on which we live, and those 

 companion orbs whereof many so largely exceed our 

 earth in mass and volume the solar system, in fine, 

 which has so often been presented to our contemplation 

 as in itself a sort of universe would seem a mere 

 point if viewed from the nearest fixed star, and yet 

 that each point of the millions which make up the 



