THE MILKY WAY 143 



thankful. The plan as well as the labour of thus 

 estimating "the contents of the heavens," and lifting 

 man's mind to a higher level than it ever attained 

 before, were altogether his own, unless we add that 

 his devoted sister Caroline shared the labour and, 

 it must be added, the dangers of the work. What 

 a vista of eternity and infinitude was unfolded by 

 the musician of Bath ! It seemed as if he had built a 

 bridge for thought to span the gulf which separates the 

 finite from the infinite, the temporal from the eternal, 

 in this incredible profusion of suns and systems, of 

 inconceivable spaces and times. 



Of the length, breadth, and thickness of these strata 

 of millions of stars that form the Milky Way, we have 

 but the faintest conception. Still, Herschel made an 

 estimate, which shows the immensity of space covered 

 by this island of stars in the ocean of infinitude, if we 

 may still presume to speak of it in these terms. " In 

 the sides of the stratum opposite to our situation in 

 it, where the gauges often run below 5, our nebula " 

 the white cloud called the Milky Way " cannot ex- 

 tend to 100 times the distance of Sirius." But we 

 know now, what Herschel did not know, that light, 

 which darts from the sun to our earth in eight minutes, 

 takes about ten years at the same rate to travel 

 the distance between Sirius and us. One hundred times 

 that distance would be traversed by light in 1000 

 years. And, if the farthest-off stars of the Milky Way 

 are nearly five hundred times as far away from our 

 earth as Sirius, the swift messenger who brings us 

 tidings of them would be five thousand years on his 

 journey, and could only tell us what was then taking 

 place, not what may be happening now, Herschel 



