Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1894-11-22
WHEN THE pAY BEGINS.
How Tune Is Measured Ivy Means OF Mcrid-
ians ot Longitude,

ians Ut Longitude,
Timc Is N>CkonCd by means " mcridi-
ans v( longitude, which are rcprnSonttd rs
Imaginary lines extending from polo 10
pole on the Carth'S surface. Whenever tho
sun is dtNctly over ono of these mcridians
ii Is noon ut all places through which tho
line passes. OF course "railrOad' or
standard" ttno must not bc coutoundcd
With actual time, for Ivy this arbitrary
though very convenient system thou' arr
only four ditfCWnt times from ono coast
IL the other, whereas, accounting Ia rial or
actual time, every town. village and city
throughout the Union has diNrNpt time
except those that happen to lie in tho
Same Nvridian AS the earth Is constant.
ly INVOLVING from west to east, il is con-
tuually bringing diforut meridian
under tho sun, and rs each passes beneath
1t tho tinNc of every place upon the morid-
Kan changes from noon tN afternoon, nr
from meridian 20 po>tmcridiau, and tho
farther away II travels tho later the timo
becomes until ii arrives ut y point directly
opposite tho sun, when IL is midnight.
From this point, then, tho meridian I've,
gins to travel toward the sun, and tho
time changes to antGmcridian until after
y
noon point, and So ON Ia the end VI time,
Fur the convenience Of mankind the cir
cumtcwucN ut tho earth is divided into
200 equal parts, known rs degrees, and tho
meridian passing through the observatory
at Greenwich in London is chosen az tho
center orstartiug point for the numbering
ot thcs, divisions Of longitude Ncuco thu
meridian Of GlVcnwich is known ns longi.
a. q
being called longitude, ono dogrro east
and tic first degree tn tho west being
known as longitude one drgrro west and
SO en-. by the time We cross tho Atlantic
and reach Philadelphia or Washington
wa have got beyond Greenwich to u dis
anco of, roughly speaking, IS degrees, or,
in other words, Washington is said to bo
in longitude - degrees west, IL, ON tho
other hand, we travel across Europe into
Asia for u similar distance We roach u
point 80 dcgoros east
ono dCErcc of longitude Is equal to four
minutes of time, or, in othor words, every
10 degrees arc equal TO an hour, So that
when meridian has passed beyond tho
sun for u distance of 80 do3yrVrS Il Is ,
O'Clock in tho afternoon ut all places on
that meridian, or It IL 10 O'Clock in tho
morning II tho meridian has Stlll 10 uc-
grccs to travel before reaching tho point
directly beneath tho SUI.
Surprising It Is midnight on July in
London, longitude naught wo will find
that in st. Petersburg, longitude 30 dc.
grrcS east, it Is = O'Clock in the morning
OF July 4, Fifteen degrees farther cast, or
longitude 40, 1T is 3o'clock IN the morn.
ing. At longitude go degrees east IL IL 4
O'Clock, and So ON every 10 degrees wa
find it an hour earlier, until finally, nrriv.
ing Mt longitude $50 degrees east, we AFRO
exactly L. hours earlier than London and
on tho other side of tho earth directly OPP.
positc longitude naught. In othcrwords,
when it Is midnight of July ut London
IL Is IL o'clock noon of that day ON lungi
tudc $50 degrees east, 1t might bo stated,
by tho way, that what we call noon Is in
reality tho beginning Of tho day and all
astronomers SO reckon -Washinutun Star.