The World. [volume] (Martinsburg, W. Va.) 1891-1896, 1893-06-01
REGULATING TIME.
Tho Intricate System OF tho Navy
Department.
An Electric spark Sets All the Islg Clocks
III the Country and Tells Us when
II u Noon in wash
ngton.

city Of Washington Is wooded hill
oycrloolSingAhe Potomac. and forming
Il part Of large government reservation
or park, which reaches down to the
rivers edge, on the top Of this hill.
remote from all the other public build
ings In Washington, stands the United
States naval observatory.
This branch Of the navy department
Il Of great service 60 the government,
i and plays d very important part ia the
j daily affairs u the country; for II Is
here that standard government time Is
rcekoned for the ,lse 81 the depart
i'ments, and for the primary purpose Of
testing and rating the chrono,neters
used on the United States war vessels,
and Ii Is from this observatory that
standard time Is regulated all over tho
country.
Precisely al noon each day It sends out
an electric signal to the various govern
ment Offices and buildings throughout
the District Of Columbia, and. by means
Of the telegraph. this Same signal Is
flashed over the United States at the
same instant.
i In order that this signal may be
sent out at the right time, II Is ncccs-
sary that the officers In. charge 81 the
4 government time service at the OBJ
servatory should know Mt Just what
instant the sun crosses the seventy
fifth meridian, or Is directly above the
meridian seventy-five degrees west
| longitude, which, rs you have learned,
h one Of number Of imaginary lines
stretched from pole to pole across the
earth's surface, and reckoncd accord
/ ing TO their distance east or west from
Greenwich. Now. this serentySIifth
i meridian has been chosen rs the stand
ard for regulating time. so that when
/ the sun gets exactly over that limo II Is
twelve o'clock ut Washington. eleven
o'clock at Chicago. ten o'clock at Dem
yer md nine o'clock at San Ierancisco;.
for. as on perhaps know, according to
| this system of standard or "railroad'
time lit being originally adopted for
the convenience Of the railroadsJ the
country is divided into four sections
Eastern, Central, Mountain and Pa
cific-each Just ono hour in advance OF
the other. and time at all places in the
same section is the same Accordingly,
when 1t Is noon at Washington 1t Is also
noon at Philadelphia, New York, Bos-
ton and every other place included
within the eastern section. This, of
course, is not strictly correct. for II II
really noon at only such places
through which the seventy fifth merid
ian happens to pass, as the true noon
| day Of place Is when the sun Is direct
| ly overhead. Washington, for example,
Il -. frss s..s.r;,1iaF ~
| two degrees farther west, and. conse-
quently, according to It's local time It
| Is only eight minutes Of twelve, while
the true time Of Boston. which Is four
degrees 10 the cast, Is sixteen minutes
in advance. But II every city we're to
use its own time. 1t would, in many
cases, give rise to good deal of confu-
sion and inconvenience: and II was for
the very purpose Of avoiding this that
the present system of standard time
was adopted.
As we have seen, the time for send-
| ing out the noon signal from Washiag-
| ton Is the instant the sun crosses the
seventy fifth meridian. This, howe Ser,
Is not the sun which gives us light and
heat. but an invisible, imaginary one,
l UECAunGt AOF CCELtthu EchbDttps tut ~ w
sun does not cross the meridian At the
same moment every day. but during
ono part Of the year he gets over It a
| little more ahead Of time each day, and
during the other part he Is correspond
| ingly behind time; and so this fictitious
sun Is used, because its apparent path
around the earth brings 1t exactly over
| the same line at the same moment
every day. Now at just what instant
| this sun crosses the meridian - deter
mined BY means Of the stars; for time
al the observatory Is not reckoned by
| the sun. but by the stars.
| Every clear night al astronomer At
the observatory looks through large
| telescope for certain stars which no
knows must cross certain hne at cer-
tain times, and BY the use Of an cleo
| tricaI machine he makes record OF the
time each star passes, as shown by q
cock which keeps sidcrcal QE star
lsfime He then consolts printed table,
which shows him &C jast--Hhnt time
Eeach star must have passed, md By as
muck asttiis tishf differs fronsthat -
corirdiby the clbch the latteris wrong.
and III that way tie sidereA clock Is
reguIstled This sihr time 8 then re-
sacel Is sun tim y " hish REG hires some.
seaIeal. slss, III l,,Er 4, = liffet eRce III
tween til II 81 Il 3sslf fur ihinnkes
81 i. ,lty. a il ys.sll tdlI8isting Of
,at .,is laa rgae than solar year,
I. u ks tho one keeping