102 THK WORLD. 



t he opposite sign, Cancer, at B. Hence, whatever sign the sun 



may be in, the opposite sign will rise at sunset, being 180, or 

 half a circle, distant from the sun. If the orbit of the earth was 

 a true circle, the progress of the sun through the signs would be 

 performed with an equable motion ; but this is not the ca.se, as we 

 have shown when speaking of the equation of time. Its orbit is 

 elliptical, and its major axis lies in the direction of a line joining 

 the beginning of August and January, nearly, so that the sun is 

 actually nearer the earth in January than in August. We shall 

 see, presently, why its rays, at that time, have less effect in 

 warming the earth, in our northern climates than in summer. 

 On account of the proximity of the earth, to the sun, in winter, 

 and its consequent swifter motion ; the sun will appear to move 

 through the winter signs faster than through the summer signs, 

 and will therefore accomplish the six winter signs quicker than 

 the six summer signs. Hence, the winter is always, in any latitude 

 north of the equator, shorter than the summer. This difference 

 amounts, in the temperate zones, to almost eight days. At all 

 places south of the equator it is summer, when it is winter in the 

 northern hemisphere, as we shall now proceed to show, and 

 hence the summer there is shorter than the winter, for the sun is 



