18 ON THE STUDY OF 



ledge, it could not be expected that the planets 

 should be distinguished from those which we now 

 consider to be fixed stars ; and it was reserved for 

 more enlightened times to suggest a system by 

 which the movements of the heavenly bodies in 

 general might be regulated. And though the 

 earliest attempts of philosophers were influenced 

 more by their common observation than by a 

 knowledge of other sciences, which since have 

 thrown so much light on the subject; yet each 

 new system, as it succeeded the other, led to 

 important discoveries, which very materially 

 contributed to that perfection in the science it 

 has since attained ; and which, under the denomi- 

 nation of the solar system, or that principle which 

 makes the sun the centre of attraction round 

 which the earth and all the other planets revolve 

 in their respective orbits, (the stars according to 

 conjecture being separate suns with a planetary 

 system to each,) constitutes the astronomy of the 

 present day. 



The utility of astronomy as a science is daily 

 becoming more obvious, and its application to the 

 purposes of navigation and geography is well 

 understood. In its progress it has led to some 

 of the most important inventions ; among which 

 the telescope, the planetarium or orrery, the arti- 

 ficial globes, the chronometer, the quadrant, and 

 many other nautical and astronomical instruments 

 bear ample testimony; while the subject itself 



