The times. [volume] (Washington [D.C.]) 1897-1901, 1899-01-29
Here is man of the date line. It will be

Here is map of the date line Il will be
observed that the line by no means follows
the 1S0th meridian all the way through
the Pacific. 1t is purely a convention. and
In fact is drawn through the ocean just
where 1t Will best serve the convenience
Of navigators and the business interests
of the regions through which it runs
The only reason why 1t should coincide
with the 1SOth meridian in any part of its
course is that most OF the sailors of the
world long ago adopted the meridian OF
Greenwich as the initial meridian; and in
sailing east or west 1t is most convenient
for them to regard the meridian that is
exactly opposite Greenwich on the other
side of the world as the line on which the
necessary change in day and date shall
be made; and the Date Line swerves from
the 1S0th meridian only when the business
or national interests OF lands lying not far
| from the line make it more convenient for
them to have ii run TO the east or west
of them. The nature of this convenience
will be explained later
But why is il necessary to make any
change of day and date? Let us consider
this question, dwelling only very briefly on
facts that everybody is supposed to know
The world revolves on it's axis from west
to east in twenty-four hours. which make
day. To measure distance east or west,
meridians of longitude have been drawn
1
east and west distance around the earth is
divided into $50 degrees of longitude In
one revolution the earth passes through $50
degrees in twenty-four hours So in one
! hour it passes through one-twent y-fourth
| of 800 degrees, or Is degrees.
| At all places that lie on the same mer-
dian midday comes at the same moment
In other words, all places on the same
meridian have exactly the same time
| Suppose il is just noon in New York city
| We know that at that moment, way out in
| the Atlantic, II degrees of longitude east
| of New York. it is exactly an hour later
or / p. m. for the sun rose at that point
| just an hour earlier than it did in New
| York and we also know that at that mo-
ment 10 degrees west of this city. in the
neighborhoOd of Lake Michigan ii is an
| hour earlier. or IL a. M. for the sun rose
there an hour later than at New York
When you reach Chicago from New York
you set your watch back an hour That is
| Chicago time. You have travelled 10 de-
| grees west and, having moved in di-
| rcction opposite that of the earth's rota-
| ton, you have, as far as you are concerned
nullified 10 degrees of the earth's rotation
and have lost an hour. If you travel west
ward clear around the world, you have
when you reach New York again nulliiied
one complete revolution of the earth You
have counted your days in sequence from
the time you left New York but you have
lost twentyfeur hours. II you steam up
the harbor on what you call Tuesday. you
will find it is Wednesday in New York,
and you must add day to set yourself
| right. On the other hand II you travel
east. which is in the direction of the
earth's rotation, you gain an hour for every
| 10 degrees you travel and twenty-four
hours by the time you return to New York
| You are day ahead of the calendar and
must subtract Il day to be even with the
world again.
Now the whole theory of the Date Line
is to have this addition or subtraction per-
| formed in the great ocean. where the sail
or and traveller are far from the haunts
of men and may make the change with
| the least embarrassment or confusion 10
themselves or others
But IL the traveller sets his watch back
| or forward every day to conform with his
! changed position. why Is ii necessary to
have any change of day or any line to
mark a change? Because the watch mere
ly marks the subdivisions OF time in day
1t has nothing to do with changes of days
or months or years.
To show the memorable necessity in or
! der to avoid confusion. of fixing upon line
| where sailors or travellers going east or
west shall understand that the calendar
day let us give "A rather striking ilustra-
ton. AT any place that is exactly 1870 de-
grees east or west of New York city OF
half around the world, the difference in
time between that place and New York is
twelve hours. Suppose two men. one trav-
cling east and the other west. might reach
that place in an instant, as we may reach
it in thought The man going east leav-
ing New York at a. m, January l. would
find the time at his destination p. m
January l. The man going west would
find the time at the same destination D.
m, December 81. At the same instant
this spot, $50 degrees OF longitude dstan,
from New York, would have two time de-
examinations differing in day, month and
year, both scientifically accurate as meas
ured by distance east and west from the
initial meridian at New York.
The question which of these dates to as
sign to the meridian on which the place is
situated Is not answered by science. 1t Is
simply matter of convenience. and
judged by that standard. 1t Is easy to see
what the date should be. The place is in