NICHOLAS COPERNICUS, 1473-1543. 



COPERNICUS, as a Polish boy, studied Latin, Greek, and mathe- 

 ^-^ matics. It was believed at that time by every one that the 

 earth was an immovable body suspended in space, and that the sun, 

 planets, and stars moved around it. The lad studied medicine but 

 was so interested in mathematics and astronomy that when an 

 opportunity arose he became a professor. Later he became a canon, 

 or priest, at the Cathedral of Frauenburg, in Germany. Here he 

 had much leisure and devoted himself to the study of astronomy. 

 Although he had no telescope, he cut slits in the walls of his home 

 and timed the movements of the planets in that way. He came to 

 the conclusion that the sun was the center of our solar system and 

 that the earth and other planets revolved around it. This was a 

 theory then, but we know it to be a fact today. 



