CHAPTER VI. 



ADVANCE OF ASTRONOMY. 



FEOM COPERNICUS TO NEWTON. 



Astronomy an Ancient Science. Astronomy is 

 usually ranked as the most ancient of the concrete 

 sciences, and this at least is certain that evidence of 

 astronomical observation is furnished by the posi- 

 tion of buildings which are much older than all 

 written records. Perhaps one of the first scientific 

 discoveries to become clear and definite was the dis- 

 covery of the year, with its fine demonstration-lesson 

 of recurrent sequences. From that unknown date to 

 the latest announcements from the observatories of 

 Greenwich and Potsdam, Harvard and Lick, there 

 extends a long procession of discoveries, sometimes 

 almost monotonous in their continuity and sameness, 

 but relieved at intervals by some great and novel 

 achievement which has given a new meaning to the 

 whole. 



That astronomy reached a stable position sooner 

 than the other sciences was partly because the sub- 

 lime subject attracted men of genius who " attended 

 their minds thereunto," and partly because a great 

 part of astronomy is concerned with simple relations 

 of distance, mass, and motion. 



Three Main Chapters. Balfour Stewart ha3 

 summed up the long history of astronomy in three 



