The Democratic advocate. [volume] (Westminster, Md.) 1865-1972, 1884-10-11
How Axact Time is Transmitted,

From the Washington Post.
The determination and transmission of
exact time forms, in utilitarian sense, is
an important part of the National Observa-
tory work. 1t is interesting to observe the
routine followed every day by the time
officer. At II o'clock he enters the chro-
nometer room and spends half an hour or
more in comparing and winding the chro-
nometers. Some of these are ready to 90
on sea voyages, while others must undergo
long period of correction. In the room
are also two clocks, meantime and trans
mitting clock. The former is never cor
rected, and when the Post reporter visited
the observatory it was nine and some hun
dredths seconds fast. 1t is never over
thirty seconds out of the way. Once
year it is taken down and cleaned, but is
never tinkered with or regulated" Every
day its error is closely calculated by the
lieutenant in charge,
At lao the error of the transmitting
clock is obtained. This is done by record
ing on chronograph both its beats and
the beats of the mean time clock If they
do not register simultaneously, the differ
ence can be determined to the hundredth
part of second. The point of lead PEN
Gil held just near enough to the pendulum
Of the transmitting clock to retard it, if it
is fast, or accelerate it if it is slow, enables
the officer to make the difference between
clocks just equal to the error of the mean
time clock, which will be shown on the tell
tale chronograph,
At IL 80 the officer signals to the watch
man on the roof and he hoists the time
ball.
At 11.56 the chronograph is connected
with the meantime clock, and the click
ing-each click represents a second-be-
gins.
Half minute later the officer turns a
switch and the transmitting clock is ready
to be connected with the out going wires.
At 11.56.44 the repeater switch, con-
Meeting these wires is closed, and the beat
of the next second, the forty-ffth, goes out,
the first signal that the hour of noon is ap-
preaching.
At $3.50 an automatic break arrange
ment causes the clock to cease transmitting
the electric current, and for five seconds
| there are no beats. The next click begins
the last minute before noon. This click is
the signal for the watchman on the roof
to slip bolt Through airing, thus fastening
| the ball.
The seconds before II final adjust
ment is made. There is a moments 81
lence-then a click as the second hand
reaches sixty, and the ball on the dome has
dropped and the hour of noon has been
flashed across the land in every direction.
1t used to be the custom for the time
officer to listen for the click and then press
key. This has been abandoned, and now
the signal flashes direct from the clock it.
self There are several telegraph instfll-
ments connected with the clock, communi-
eating with the several telegraph companies,
the fire alarm bells, and by private line
with clocks in the War, State, and Navy
Department, White House, National Muse
um, Clerks Office United States Senate,
Government Printing Office, Interior and
Post-office Departments city post-ofice, the
Pension Office, Treasury Department, At
torney-General's Office, and the headquar-
ters or the Surgeon-General The Signal
Office also gets the correct time.