460 



GENERAL SCIENCE 



and the time of all places east or west is earlier or later than noon. 

 The same is true of every hour of the day for this place and other 

 places east or west of it. This makes confusion in the arrange- 

 ment of time tables, and in the running of trains. In some places 

 this time is still used, and is called sun time; and the time by 

 which the trains run is called train time. 



Latitude. Not only is it necessary for ships and people to know 

 their distance east or west of the prime meridian, but also to know 

 their distance north or south of the equator. For this reason the 



FIG. 352. Degrees of latitude and parallels by means of which points are located 

 on the earth as north or south of the equator. 



earth has been divided into imaginary circles running around the 

 earth parallel to the equator. The equator is an imaginary circle 

 midway between the poles which is marked zero (0) latitude. The 

 distance from the equator to the north pole is divided into 90; 

 likewise the distance from the equator to the south pole. A person 

 in Maine, Ottawa, Canada, Michigan, Oregon, etc., is in 45 north 

 latitude or one-half way to the north pole from the equator. A man 

 in Central Illinois, near Springfield, is in 40 north latitude and 90 

 west longitude. At 9 o'clock in the morning in this place, it is 

 3 o'clock in the afternoon at Greenwich. 



