TIME AND LONGITUDE.

New Zealand Times, Volume XXXIII, Issue 5456, 21 September 1878, Page 3 (Supplement)

TIME AND LONGITUDE.

There is an old aud instructive problem which I have lately propounded to several people, and have been struck by the great variety of answers giveh to it. Although we often lose sight of the fact, it is nevertheless true, that any given day or year does not begin all over the world at the same moment, but, commencing first at some point in the east, it travels round westward with the sun, so that two different years are often co-existent at tho same moment, and it is easily possible for two events to occur a few hours apart, and yet that which happened first to occur in 1878, and the latter event in 1877. In the same way each day of the week starts somewhere to the eastward of us, and dies somewhere in the west. Taking, then, any given day of tho week, as Monday, the problem is’: When and where did it end, and how long did it exist ? Or, to pnt a similar question, Where did the year 1878 first commence, and at what Greenwich time 1 I will simply state my belief that last Monday commenced in New Zealand somewhere about noon on Sunday, but not at noon,.its commencement at that time and place being in no way connected with its position aa bur antipodes, but being a mere accident of civilisation. If the whole northern hemisphere should become civilised and inhabited, the day would then almost certainly commence at Behring’s Strait, and would last 48 hours. A person crossing Behring's Strait east or west would gain or lose a whole day just as he now .does by sailing round the globe, so that he might easily cross over and spend a few horn's of to-morrow with his friends, and return in time for dinner, or might enjoy the New Year's Eve on two successive nights. If the Pacific Ocean became inhabited land, a meridian would have to be chosen as a starting point for the day, and a person stepping across this imaginary line would gain or lose a day. At the same moment that Sunday morning was commencing on one side of this line, Monday morning would be commencing on the other, and there would be constantly two different days going on side by side, with 24 hours’ difference of time between them, though only a few yards apart. It would be possible for a person standing astride this line to have for au instant one foot in Monday morning, the other foot in Monday night, and Lis body in the previous Sunday. I purposely avoid giving any reasons, and do not assert that all my views are correct; but I throw out the problem as ah amusing one for argument and discussion, as it abounds in apparent paradoxes. At the same time it cannot fail to be instructive. LaTIMEB CLARK.