ARCTIC AND ANTARCTIC REGIONS 403 



is midway between San Francisco and Manila. Approximately there are i6o 

 meridians between New York City and Manila via San Francisco, so there 

 would be 200 meridians between the two places via Europe and Asia. Di- 

 vide 200 by 1 5 as explained above and you have the difference in time between 

 Manila and New York, which would be 13 hours, and 20 minutes. 



LATITUDE. 



Latitude, in geography, the distance of any place on the globe north or 

 south of the equator measured on its meridian. It is called north or south 

 according as the place is on the north or south of the equator. The highest 

 or greatest latitude is 90°, that is, at the poles; the lowest or smallest o, at the 

 equator, between which and the poles are the parallel circles, called parallels 

 of latitude. One method of finding the latitude of a place is by measuring the 

 altitude of the pole-star. When the latitude and longitude of a place are 

 given its position on a map is easily found. 



HOW A DAY IS LOST OR GAINED. 



One difficulty that may lie in a matter apparently so simple as the 

 reckoning of the days of the week is well shown in one of Poe's stories. The 

 obdurate father of the maiden — evidently with the Greek calends in mind — 

 promises to give her to the objectionable swain when three Sundays occurred 

 in one week. To his consternation, and the joy of the lovers, thh seemingly 

 impossible event indubitably happened when two sea-captains appeared to- 

 gether upon the scene who had circumnavigated the globe in opposite direc- 

 tions. As a matter of fact, this bit of fiction represents what is taking place 

 every day in the year, and must continue to occur as long as our present 

 method of reckoning time is retained. And the reason for this is simple and 

 familiar. The civil day begins and ends at midnight, but for convenience 

 of explanation let us assume (as in the practice of astronomers) that the day 

 begins at noon and ends at the following noon. It is clear that the interval 

 of time between two successive noons will be, for us, twenty-four hours (or 

 a day as measured by one complete rotation of the earth) only when we 

 remain on the same meridian. For if at noon on the beginning of Monday 

 we move, say, over a space of fifteen degrees toward the east, it is obvious 

 that when the sun again stands at noon, for us, only twenty-three hours will 

 have lapsed, since we shall have accomplished one twenty-fourth of his 

 journey for him; that is, Tuesday, will begin, for us, one hour too soon. 



