DECEMBER 137 



ut it somehow thus : " that week in which the almanack 

 tells us the days are growing shorter, though the sun sets 

 at a later hour." Of course the afterwoow does not grow 

 longer. Noon is the moment at which the sun crosses the 

 meridian, and it then attains its highest point for the day ; 

 and of course if it rises later, it also sets earlier. The 

 apparent anomaly occurs thus the solar day, which is 

 measured from the time the sun crosses the meridian on 

 one day to the time it does ditto on the next, is not of 

 uniform length. The reasons which you need not read 

 are : (1) The path of the sun does not lie in the equator, 

 but in the ecliptic ; (2) owing to the earth's orbit not being 

 circular, its motion in the ecliptic is not uniform. Now it 

 would manifestly be very uncomfortable to have days of 

 varying length, therefore an imaginary sun has been in- 

 vented which is supposed to behave in a decent and 

 orderly fashion ; the time by him is called " mean time," 

 and is that shown by a watch. The time shown by the 

 real sun is called " apparent time," and is that shown by 

 a sun-dial. The difference between these two times is as 

 much as sixteen minutes at certain seasons of the year. 

 Now on the shortest day the sun'crosses the meridian nearly 

 two minutes before twelve o'clock. He was earlier the few 

 days before, therefore his time of setting was earlier too. 

 Suppose that on December 21st apparent noon is at 

 11.58 A.M. and the sun sets at 3.51 P.M., and on Decem- 

 ber 14th the apparent noon is at 11.55 A.M. and the sun 

 sets at 3.49 P.M. Now the afternoon on December 14th 

 is one minute longer than on December 21st (3 hours 

 54 minutes to 3 hours 53 minutes), and yet the sun has 

 set two minutes earlier (by our watches).' 



December 20th. Another beautiful afternoon. Such 

 clear yellow skies ! To me the top twigs of Holly bushes 

 against a primrose sky recall, oh ! so many winter days in 

 the past; long walks through bare woods and rustling 



