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It appears also to us to move every year obliquely 

 from west to east, coming twenty-three degrees and 

 a half to the north, and then going just as tar to the 

 south. 



2. Some of the stars keep always the same distance, 

 \vith respect to each other, and are termed fixed. Others 

 are continually changing their situation, .whence they are 

 termed planets. Two of these, Mercury and Venus, 

 are frequently between the earth and the sun : of which 

 the former being generally hid by the rays of the sun, is 

 seldom visible : but Venus, commonly called the even- 

 ing star, is very conspicuous. The earth is never be- 

 tween them and the sun. They are sometimes between 

 us and him. Sometimes the sun is interposed between 

 us and them. 



3. The upper planets are Mars, Jupiter, and Saturn. 

 The sun is sometimes between these and the earth. But 

 none of them is ever interposed between the earth and 

 the sun. Mars has different appearances, like the moon, 

 as it is differently situated, with regard to the sun : 

 whereas Jupiter and Saturn always appear with the same 

 aspect, ar.d have smaller planets revolving round them. 

 All these revolve round the sun, in their several stated 

 periods. 



4. Beside these, there is another kind of stars called 

 comets, vulgarly blazing stars. These do not revolve 

 round the sun, in so regular orbits as the planets. The 

 fixed stars are above these: about 2200 are visible to 

 the naked eye. These have a vivid light, and always ap- 

 pear with the same face towards us: they seem to have 

 a twofold motion, a slow one from east to west in a 

 year, and a swift one round the earth with all the other 

 stars in four and twenty hours. But there are some of 

 them which never set, namely those near the north or 

 south pole. 



5. To explain these phenomena of the heavenly 



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