Evening star. [volume] (Washington, D.C.) 1854-1972, 1901-03-30
How Word is Sent Out From the
Naval Observatory.
SETTING HHE COUNPRY'S CLOCKS
instruments of Wonderful DeIicacy
and Precision.
DROPPING THE TIME BALLS

Written for The Evening Star.
There are 10000 clocks set by the gov
eminent every day when the noon hour
strikes in Washington In every large city
throughout the United States time balls
at the same minute indicate the time to
hundreds watching for their fall and hun
dreds of watches are regulated to corre-
spond with the signal. This time service
comes from the naval observatory in Wash
ington, and its original design was to fur
nlsh mariners at seaboard cities with the
means of regulating their chronometers
Like great many other government in
stitutions. 1t has strayed from its origi-
nal purpose and now 1t serves another Of
more general usefulness There Is strong
national feeling against paternalism in the
United States. but there are many small
ways In which paternalism fourishes with
out hindranCe.
This time service is ostensibly free; ac-
tually it Is not free, but costs the owner
of each clock SIS a year. The government
furnishes the signal Free but the govern
string wire to the naval observatory
from your Office in New York, or Chicago,
or San Francisco, the Navy Department
Will furnish you the signal every day with
out money and without price. But the
strinSfng Of wires is costly and attended
with great difficulties. So you necessarily
turn to the telegraph company, with it's
$4,000 miles OF wire; and this company
puts a wire into your office and connects
IT with Its great system which has a wire
running to the observatory. No one knows
what the company receives from its time
service, but reckoned on a basis of SIS a
clock each year and 10000 clocks, the
amount should be more than a million
dollars. This sum it receives for suspend
ing all business on its wires from IL 81 to
" o'clock. Washington time. each day. and
nrar tor f1n
tory full control Of them. Actually the
operator there does not send the signal
1t Is sent automatically by a remarkable
clock-and so far as the time balls are
concerned, the preliminary work is done
by man In charge OF each, who HOSTS 1t
to position and throws its machinery into
the circuit just before the final signal goes
out
At the Naval Observatory.
The naval observatory contains great
many fine instruments 1t holds what was
for time the largest telescope in the
United states-the 26-inch Clark equatorial
which cost $4,000, and was erected in
1873. The Lick telescope in California, 49,
inch. soon took from the government the
distinction of owning the greatest -tele-
scope. and that in a few years was exceed
ed by the Yerkes telescope 40 inches With
the Clark telescope Prof. Hall discovered
the satellites of Mars. and there are other
discoveries to its credit In astronomical
history.
The big telescope has nothing to do with
the time signal. The telescope used in the
business of measuring time is the transit
instrument which Is much smaller. Here,
on each clear night, an observer watches
the movement OF the stars, and by their
aid corrects the big Frodsham clock which
stands in the signal room. In the making
of the observations the web of the spider
plays an important part. Threads of cob
q mot nnt fin hut rdnrF ,,11x
strong for their fineness. They also pos
sess a remarkable stability, not being
affected by moisture and neither expanding
nor contracting with changes in the tenn
perature. These threads are used to make
cross lines extending at right angles across
the field OF view so as to divide it into
mathematical spaces. For this purpose it
is found that spiders webs gathered near
Washington are more efficacious than those
which can be obtained elsewhere. Some
years ago the directors of the observatory
sent to China for webs. thinking that the
large spider Of that country would produce
especially desirable web But it was
found that in their peculiar field the Amer
lean spiders We're superior to the foreign
another triumph for home industries. The
Washington spider webs are obtained by
expeditions sent out in June of each year.
They collect from barns and fences the
cocoons of big 'turtle-back'' spiders. Each
cocoon Is wound with single f1lament,
and this is reeled off and used to divide the
telescopes field Of view. By their aid the
observer measures the movements of the
stars and determines exactly the time. The
big clock is regulated to the minutest
measurable fraction Of a second and left
to feel it's measured way through the hours
till morning. 1t is not affected by any of
the movements that jar tall buildings and
shake smaller ones, for it is secure on
deep-sunk pedestal of granite
Regulating Chronometers.
All through the signal room as the day
hoppers In the field On warm summer
day. This is the voice of the chronometers,
which fill long wooden cases. All the
navy's chronometers are sent here to be
regulated.
Opposite the Frod sham clock are two
less costly timepieces. which contain the
mechanism for sending out the time sig
nal. These timepieces cost between $500
and $500 apiece There is. by the way an
other clock in the observatory, for which
Congress paid $4,000. II was invented by
DR.. John Locke of Cincinnati in 1S49 and
was the first apparatus for transmitting
time automatically. 1t is running now but
its only use Is to measure time
The 'Frodsham clock is set for sidereal
time. Between this and standard eastern
time there is difference of 8 minutes
1903 seconds. The other clocks, when they
are regulated by the Frodsham, must be
made to vary just minutes 12.09 seconds
from it. This is accomplished by an in
SenlOuS recording device. A cylinder
standing on an adjacent table is made to
revolve at a fixed rate Of speed. A sta
tionary pen loaded with red Ink makes a
straight mark on the paper which is fas-
tened around this cylinder. In each Of
the two clocks is a cogged wheel Just behind
the dial which turns with the second hand
Each Of the cogs in turn touches a brass
spring which closes the circuit of a
battery. An electric impulse from this
battery passes through the pen and by
a mechanical arrangement causes it to
make a horizontal mark on the cylinder
Thus every second is permanently record
ed. The Frodsham clock is also in circuit
with this pen. A cup OF mercury rests
in the clock. 1t is connected with one pole
Of the battery. The pendulum is connect
ed with the other. AS the pendulum swings
1t touches the mercury in the cup closing
the circuit and sending an electric impulse
through the pen. This impulse also causes
the pen to be DETECTED and to leave
mark on the cylinder.
A Delicate Task.
1t is easy enough to set. either of the
other clocks within a second of the Frods-
ham-to set the minute hand at the eight,
minute variation and the second hand
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