Evening journal., 1901-11-06
LET'S COUNTRY KNOW
WHEN NOON HOUR ARRIVES S

es through the pen and by mechani-
cal arrangement causes it to make a
horizontal mark on the cylinder. Thus
every second is permanently recorded.
The Frodsham clock is also in circuit
with this pen. A cup of mercury rests
in the clock. 1t is connected with the
pole of the battery. The pendulum is
connected with the other. AS the pen
dulum swings il touches the mercury
in the cup, closing the circuit and send
ing an electric impulse through the
pen. This impulse also causes the
pen to be DETECTED and to leave a mark
on the cylinder.
A DELICATE TASK
1t is easy enough to set either of the
other clocks Within a second OF the
frodsham-to set the minute hand at
the eight minute variation and the sec
Ond hand twelve seconds more. But
the fraction of the remaining second
must be measured with great nicety.
rms Is done by measuring the space
between the marks on the cylinder
with a prepared graduated scale which
shows the difference between the two
beats to hundredths of a second. The
operator doing this accelerates OF re-
tards the clock to be regulated by
touching the pendulum with his finger
till the space measured shows that the
fractional difference is Just nine
hundredths of a second Then the
clock is ready for the days work.
All this takes place not too long be
fore the noon hour. so as TO give the
clock little time to lose or gain.
There is a sounder on top of the clock
which steadily ticks off the seconds
loud enough to be heard in the adjoin-
ing room. At three and a quarter
minutes before noon approximately the
big clock is switched into the telegraph
circuit.
THE SIGNAL CLOCK
This signal clock has toothed
wheel directly behind the wheel which
marks the seconds. The wheel is di-
vidcd into sixty spaces, but the tooth
representing the twenty-ninth second
is missing, and so are those represent
ing the thirty-fifth. fifty-sixth, fifty
seventh. fifty-eighth and fifty-ninth
seconds. AS this wheel revolves the
teeth come in contact with a spring
which is in connection with the cur
rent. closing the circuit and causing
the sOunder to respond. The twenty
ninth signal drops out, and that inter
mission indicates the approach of the
half minute. In the same way, an in
termissiOn of FIVE beats indicates the
approach OF the end OF the minute.
This arbitrary arrangement is designed
to warn operators all over the country
when they cut in at just what point
they have come on the circuit Be
fore the final signal there will be a
lapse OF twenty seconds. This is
brought about by the action Of the
operator at the observatory, and is not
automatic like the other intermissions.
IL is produced by the operator moving
the switch key, which throws out OF
thee ircuit the wheel marking the sec.
Onds and throws into circuit
The wheel uhat marks the
minutes. II an operator comes in on
the circuit the wheel marking the sec
he notes is a single second, he knows
that he has come in on the half min
ute If the intermission is five seconds
he knows he has come in just before
tie minute. but not the final n:n-
ute. If he counts more than
hve seconds. he knows that it is the
final intermission before the noon hour
and he acts accordingly.
DROPPING THE TIME BALL
What this operator and what al
operators have to do in regulating the
time ball is to turn a switch between
the sounding of the fortieth secOnC
and the signal which marks the tina
minute AS soon as the operator has
counted more than five seconds in th'
iintermission he knows that the mex
signal will make the exact hour o.
noon. The time ball has been hOiste'
to it's position at the top Of the pole.
These poles are in conspicuous places
in every large city in the United States
usually on the top of the Westerl
i Union Telegraph building. The bal
is Of canvas over a glObular form
There is a mechanical device by wnicl
a single impulse sent over the wir
when the time ball is in circuit pull
the trigger and releases the ball, so tina
it falls to the bottom Of the pole Il
the intermission which he knows pre-
/. ttu6S llt undA ciblldif lub OpNA eApo
throws the switch, and in this way al
the time balls in the country ar
brought into the circuit with the Nava
!; Observatory.
WHEN NOON ARRIVES
In the last Tooth of the last second @
1.-THE ffty-ninth minute OF the .elevent
hour at Washington the tooth of tn
big minute wheel touches the sprin
which closes the circuit, and simultf
Z neOus.y the time balls all over the cour
S try drop When simultaneously is sai'
! of course no allowance is made for th
E fraction of a second during which IN
4 electric impulse is going out trol
S Washington. Such an impulse ha
been sent from Washington to Sa
D Francisco in one-fifth of a second.
D The dropping of the time ball sci
e the clocks on Governors Island, one
t the military posts at New Yorl
g | through the intermediary of a bug
e l. call. Just before noon of each day tw