Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1893-06-04

| electric circuit as each tooth passes small
epring. which keeps 1t closed. lhe hfty-
ninth tooth il omitted. so that no signal IS
qiyep out at this bea. A stud projects
from the side of the siStietn tooth. when
acts on another spring. giving signal az
the sixtieth second only. Tho pendulum ~
a mercurisl compensation. the jar OF which
ia OF steel, containing about forty pounds or
mercury. The rod passes down through
the cap of this Jar INTO the mercury: A
vornier is placed about the centre OF its
length for tho purpose Of reading It's arc OF
vibration. The dial is engraved and sill
vered. IL il divided INTO three circles, the
largest (nearly the full SIZE of the dad INTO
sixty minutes the one above the centre or
the dial into sixty seconds. and the circle
below the centre into tWentY-four hours.
A glazed head-piece covers the movement
and admits OF all parts and connections
being seen.
TRANSMITTING TINE.
After these standard clocks are once adj
iusted they are never touched again cx-
cent 10 wind them up. Any error Is adj
iusted in the electric clock by means OF
which the time signals are sent out over
the country. The error. # any, u obtained
from the Nautical Almanac. which has the
exact time of the transit of ell the heaven
w bodies which are visible from gwen
points of observation calculated tor seVe-
raj years ahead.
The svstem of transmitting this time by
means If electric signals 70 all parts OF the
country simultaneously and the device
known rs the cnroDOgraph. by means or
which any two clocks. no matter how Tar
auar;, can be compared. are the EXHIBITS
which excite the greatest amount Of lnte-
rest among visitors.
Some IDEA can be obtained OF the extent
OF the usefulness OF this system wnen 1t IS
known that the ends of an electric circuit
over $40. 900 miles inlcngth terminate IN he
little observatory IN Jackson Park. THIS
wire is connected with electric clocks IN
every CITY Of any importance IN the United
States. For the three minutes preceding
noon each day Washington Obserya-
tory time) all work u suspended on
the Western Union wires throughout tho
country. and bv means Of switches the sec
ond beats Of tho electric clock NJ the nava!
observatory are transmitted simultaneous
j. to all parts Of the country. 10 aid COM
parsons. where there Is no chrouOcraph
the twenty-ninth second Is omitted IN or
der 10 emphasize the striking of the bait
minute. aud five seconds are omitted be-
fore each minute except Tor the hour OF
noon. before which the last ten seconds
are omitted for the same purpose.
Tor THE GENERAL PUBLIC.
Where there j. n chronOgraph the naval
observatory AMI the clock 10 be compared
are both switched on 10 the instrument.
By means OF an index attachSd 10 the
armature of magnet and revolving CYL
Under the beats OF each Of the tlmcplcccs
are recorded. and the distance be-
tween the marks made by the index
shows the difference N time between
the two clocks. Besides these de-
vices tor asccTtalnlng the difference be-
tween the local tlmeplece- and the stand
ard clock AZ the naval observatory there
j. anothertur the general pubic. ms de-
vice consists OF o ball mounted on stan
on some high building, and then by means
of an electric device, which can be switch
cd INTO the Washington circuit lust be-
fore the stroke Of T. O'Clock noon. the ball
Is dropped ON the stroke OF that hour by
the observatory ciOcN.
This impulse furnished BIZ the stroke Of
noon drops timc-balls III Washington. Bal
tlmore. Philadelphia, New York. Boston,
Holmcshou. HAMPTON Roads, New Orleans.
and viii N a few DAYS cause the big ball on
the government building 10 drop al that
moment. Hundred, OF thousands OF
watches ara daily compared by dropping
Of these balls. and III some Of the eastern
cities II Is no uncommon sight II see
groups of several hundred people watch
ing with watches III hand for the bal tn
drop.
While this system is of great conye-
nieuce 10 the general public 1t is an abso-
Lutte necessity for the long lines Of rail-
road III this country under their systems
of operation. When there are long lines
OF single track, Is there ar on many Of
the western roads. II would be almost I'M
possible 10 prevent accident ~ collision
were II not for the ability to constantly
compare the time pieces all over the line
with some common standard at simuta-
ncOus intervals.
This system was devised and perfected
by Professor Gardner. of the naycl-oO-
servatory staff, and very appropriately
hnArs his nAmp.