MOTION OF THE SOLAR SYSTEM. 9 



wo.rlds in the course of formation worlds destined after in- 

 calculable ages to become the seat of sensitive and rational 

 beings. 



At the beginning of the present century, the fixed stars, our 

 sun among the rest, were still supposed to be immovable, since, 

 as far as our astronomical annals reach, no change has ever 

 been observed in their mutual positions ; but the wonderful 

 precision of our modern instruments, and the progress of astro- 

 nomical observation, have taught us that they by no means 

 deserve their name. As we and all our brother-planets are 

 circling round the sun, thus also the sun with all his satellites 

 careers through space at the rate of 800,000 miles a day; 

 but the time of observation is as yet too short to be able to 

 ascertain the centre of hig prodigious orbit. Similar motions 

 have been discovered in other fixed stars, and thus we can hardly 

 doubt that all the spheres of our world-island are engaged in 

 constant motion nay, that our world-island itself revolves round 

 another, and that thus eternal motion pervades all the recesses 

 of the universe. 



The enormous swiftness of the fixed stars gives us an over- 

 whelming idea of the vast proportions of the starry heavens. 

 Every minute they leave several hundred miles behind every 

 minute we are carried along with the sun at the same prodigious 

 rate through the celestial regions ; and yet the starry firmament 

 appears constantly unchanged, as it did to our fathers before us. 



This boundless prospect into space opens to us a no less 

 boundless vista into time, for the sight of the distant heavens 

 does not exhibit their present but their past condition. The 

 rays of light which bear witness to the existence of these worlds, 

 circling in their unfathomable depths, have many of them 

 required millions of years to reach our planet. Many of those 

 brilliant orbs might have become extinct ages ago, and yet their 

 rays, sent forth up to the moment of their destruction, would 

 still announce their past glory to countless worlds. Thus with 

 every improvement of the telescope not only the magnitude, but 

 also the age, of the visible universe increases ; and as we dive 

 deeper and deeper into the abysses of celestial space, we also 

 plunge deeper and deeper into the ocean of the past. And if 

 we could fly to those islands of light, which even our giant 

 telescopes are scarce able to reveal, we still should be only on 



