360 GENERAL SCIENCE 



with it or not. It is more convenient, and in all ways more 

 practical, for all the people in any certain section of country 

 to have all time-pieces read twelve o'clock when it is noon 

 at places situated on some one geographical meridian chosen 

 as a standard. By having these standard meridians 15 

 apart the time-pieces in adjacent time-belts will be exactly 

 one hour apart. A traveler going from one such section into 

 another will change his watch reading just one hour at some 

 convenient or established place, leaving the readings of the 

 minutes and the seconds unchanged. If the traveler jour- 

 neys eastward, his watch is set ahead an hour for every change 

 from one time-belt into another in order that its readings may 

 conform to the time of the belt into which he has come. In 

 going westward the watch must be set back an hour each 

 time. 



It is interesting to note what befalls a traveler in the 

 matter of time-keeping who makes long journeys east or 

 west around the earth. If changes of one hour at a time are 

 made from time-belt to time-belt as discussed above, the 

 watch readings will conform always to the times of the 

 places where the traveler may come. But confusion soon 

 arises as to what day in the week it is. 



The day period from noon to noon (or midnight to mid- 

 night) is lengthened in going westward. The traveler has 

 need to set his watch back one hour for every 15 passed 

 over, and while the time at the place whence he started 

 might show one whole day passed, the traveler's watch after 

 being set back shows but twenty- three hours passed. He 

 has "lost" an hour. To travel 30 westward means a read- 

 ing at the place where the journey began two hours later 

 than at the place where the traveler then is, or two hours 

 lost. To complete the 360 of the earth's circumference 

 and the twenty-four changes of watch that this requires 

 involves the loss of one whole day. In other words, at the 



