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ASTRONOMY. 



Of the various brandies of science cultivated by 

 mankind, astronomy is one of the most important 

 and useful. Our faculties are enlarged by the 

 grand ideas it excites, and the mind is exalted 

 above the contracted prejudices of the vulgar. 

 By the knowledge of this science, we discover the 

 bulk of the earth, and ascertain the situation and 

 extent of the countries and kingdoms into which 

 it is divided : by aiding the navigator, and facili- 

 tating his passage through the trackless ocean, 

 commerce is carried on to the most remote parts of 

 the world. 



Upon examining the heavens, the first and most 

 obvious phenomenon that presents itself to observ- 

 ation, is the apparent diurnal motion of the sun, 

 moon, and stars, or that by which they are seen to 

 rise and set once in twenty-four hours. 



If, to consider more attentively the circum- 

 stances of this diurnal motion, you place yourself 

 in an elevated situation, you perceive a circle ter- 

 minating your view on all sides, by the apparent 

 meeting of the earth and heavens. This circle is 

 called the horizon : it divides the heavens into two 

 parts ; that which is above the horizon only is 

 visible ; and this appears to us like a concave 

 hemisphere, which we call the sky, in which we 



