The sun. [volume] (New York [N.Y.]) 1833-1916, 1898-06-05
JUGGLING WITH A DAT.
PEzgEBs OFFERED M a OROORED
INTERNATIONAL DATE LINE
what nay Is n Mere when II us snHaay IN
NHnnila and hosdRy IN nasnG ukepG -
Rather Hard 70 keop atraIHhtenea Opt.

NannIa ana aosdRy IN nssnG Hksas -
Rather Hard 70 Koep atrsIEstenea Out.
From the BOSTON Herald
Every one knows that when IL is midday with
us IL 10 midnight at every place on dramatically
tho opposite side OF the globe. In other words,
the difference between our time and that Of a
place 80 situated is exactly twelve hours. Bonn
bay 10 a place so situatod-very nearly-with re-
lation TO Boston. The clocks of Bombay and
those OF Boston indicate the same hour. though
In different halves Of the day. Thus when II 10
s A. NJ. in Bombay 1t is 8 T.. NJ. In Boston; "a.
NJ. in bombay, 8 L. NJ. In Boston, and 80 on
around the dial.
Just now all eyes are turned upon Hong Kong
and Manila. which arc situated very nearly,
but not quite half way around the globe, the
distance being rockoned westward. The diHor-
ence in time between Manila and Boston is
eleven hours. When n Manila clock indicates
3 A. NJ. the time with us is 1 p. NJ, and the
same difference holds of every hour, OF course.
To change Manila time to Boston time. there
fore, we must add eleven hours, treating the
case Es though tho Manila clocks were that
much slow. Thus, II we hear that a certain
event took place Mt Manila at 10 \. NJ, we can
figure out at once that 1t was then y y. NJ. with
us: IL the event Is sail to have nppcned at4
p. NJ, then it must have happened while we
were asleep. or should have been asleep. at 3
o'clock in our morning.
Thus far the reckoning is easy. But now
comes "A very important question. which, unless
it's answered corTe, tlr, may put us IN error
twonty-iour hours al TO tho time OF OCCURRENCE
how about the uny OF The month AMI week TINS
matter is not so $ ,mpi' as 1t may seem at Hrst
sight. for here again we must III ko - "COrrcc.
tlUr.' and unless we arc cleaT-hea ted W" shall
MAKE mistakes sometimes. In fact, it makes "a
difference, which We III asst allow for, whether AN
event is dated in Manila lime or in that OF Hong
Kong.
For example. amoag the c..ble8rans first re-
ceived by us relating to Commodore DeMey's
%yigtory, IN Manila Bay WIS one dated Hong
Us 1t proved, the BON Oardmcnt OF Mania. sup
posed to be th.n taking, place. The day, was
Kong it, was Monday. though the actual differ
ence in time between the two places is less than
half an hour. What day WAS 1t, then. with US !
The answer OF this question depends uton he
location of the international d,te line. The
fact is well SHOWN that there Is here IN
ing which one must make n change in his rcck-
oning of time. Ii he crosses IL from east to west
day must Ic rcpeRtcd. Til 8 line is the isOjh
meridian OF longitude cast or ives, Of lhc
prime nerialnn" OF Greenwich. In other
words. it is the meridian OF Ion !ituAe which
lies half way nroumi he Globe from Greenwich.
SIDES SIDE "" off tbs bis i nnt"' when It Is $" on
the cast side u Is Monday on the vest
sfiS; r, w 6SH o =, ,b rs w MSh sidyo. and so@ an " thro s,aS
the week. ANA there IS, of course, Inc same dii-
ference In the days Of the month. h. lsl OF May:
u ISltlSt III Wv StoN Si'tts wins WV - VI
May on tho west 81 'e. ami so On. though actu'
ally it Is one and the same day.
The reason tor this peculiar state OF things Is
that this is the line at which, by tho ComInon
consent Of the commercial nations, The day is
considered to begin. IT, is not easy to MAKE per.
some such arrangements: but tho mystery may
be cleared up partially In this way:
suppose a person, starting from Boston on
Sunday, were to travel around the earth In n
westerly direction in some magic conveyance as
rapidly as tho sun in its diurnRl course travels
or seems to travel in the same direction. He
would accomplish the journey in twenLy-four
hours. and. having started on Sunday. he might
the way around-that 10, II he took no note OF
timc-tor the sun would emain above the
horizon throughout the journey. Yet when
he reached Boston at the end of twenty.
four hours it. would be Monday; No doubt
about that. Clearly, at some point in the flying
Journey he should have changed his limerick.
oning. He should have said to himself: Thus
viii call the day Monday. Had he done this he
would have come out all. right. The 1S0th
change. since it lies almost wholly in tho ocean,
where u double.nRmed day nobody.
Were this matter being treated here merely
in o general way. no more need be said. But
Philippine Islands. an important, note must be
added. Although the date line is commonly
stated to be the 1s0th meridian of longitude,
and is practically, SO regarded by navigators,
actually, MS IL is laid down on a chart, 1t docs
not follow this meridian. but it takes II long
sweep to the wcst and curves around tho Phil
| ippine Islands. bringing them on its eastern side,
Notwithstanding that these islands lie some SO
degrees Of longitude west of the theoretical date
line.
This exceptional position of the Philippines
with reference to this limo may have originated
in tho circumstance that Magellan discovered
them while sailing westward. and that the way
of reckoning time there had become established.
owing to their early settlement. before n date
line" was thought of: but whatever may be the
reason for IL, tho exception is q matter to be
born" in mind in dealing with Manila time. 1t
is this position OF the date line which causes an
apparent difference OF twenty-four hours be-
| tween tho time OF Manila and that Of Hong
Kong, although the actual difference is less
than half an hour.
To end with tho practical bearing of the points
here given, in figuring upon Manila time. as it
VIII probably come to us frequently in tele.
grams. VIC must regard it as eleven hours slow
with reference tn Boston time, as already stated
and illustrated-must add eleven hours TO the
Manila time. even though it lanes us in the sue
cccding day, as will be the case when an event
has occurred at ! p. NJ.
Hong Kong time. on the contrary. must be
treated as fast with reference to our tine, about
twelve and onc-half hours.
Thus, IL we learn that IL certain event. the ar
rival of u ship, for instance, occurred at Hong
Kong at the hour of noon on n certain day, we
are to understand that IL occurred when OUT
clocks indicated ll:30 i. NJ. on the preceding
day. A telegram announcing the event, IL sent
at one. would be received by us In he course OF
J AN hour or less, and but for the bit of headwork
here laid out 1t would soem to reach uS several
hours before the event occurred.