2 86 EIGHTEENTH CENTURY. PT. in. 



and not that all other things are in motion ; therefore Her 

 schel concluded that the reason of the apparent change in 

 the place of the stars was the real movement of our sun and 

 its planets among them. 



But, if such were the case, then there ought to be on i 

 point straight in front of our path which would not appear 

 to move ; for if you walk into a forest, you will observe that 

 the trees on either side appear to spread farther and farther 

 apart as you approach, but that those exactly in front of you 

 will not seem to change their places. Now Sir W. Herschel 

 found one point in the sky, in the constellation Hercules, 

 where the greater number of the stars do not appear to move, 

 while those to the right and the left seem to be gliding off 

 each in their own direction. He therefore concluded that 

 our sun is carrying the earth and the other planets straight 

 towards this point in the constellation Hercules. The rate 

 at which this movement goes on is not accurately known, 

 but it must be very great, probably at least as much as 

 150,000,000 miles every year. 



And here we must leave the discoveries of this great 

 astronomer, although we have only glanced at them very 

 superficially. The immense strides in astronomy made by 

 Laplace, Lagrange, and Herschel cannot be understood in a 

 moment ; and I wish you always to remember that you can 

 only gather crumbs of knowledge from this book, which 

 may, I hope, lead you to long and seek for more solid food. 

 Before, however, we take leave of Sir W. Herschel, we 

 must not forget to mention the faithful assistant who was so 

 great a help to him in his labours. 



When George III. gave Herschel his home and pension, 

 the astronomer sent to Hanover for his sister Caroline, and 

 she lived with him and received a small salary as his assist- 

 ant She shared his night-watches and mapped down the 



