Evening star. [volume] (Washington, D.C.) 1854-1972, 1904-07-08
MAKING GIANT TIMEPIECES.
Dials Commonplace in Position, but
Ponderous Pieces of Mechanism.

Ponderous Pieces of Mechanism.
From the London Mail.
l suppose there Is no more famous clock
in the world, none whose name would be
more readily recognized when mentioned
wherever the English language is spoken,
than Big Ben" at Westminster. Really,
1t is not the clock itself that is so called
but the great thirteen-ton bell on which
the hours are struck. but few ever refer TO
the clock tower and it is 1.-The time by Big
Ben" that is asked for when the exact
hour is wanted.
And there is object more looked up
to- in London Its altitude of 800 feet de-
tracts. however. from the visitors aston
ishment at its size. for it looks but a small
affair from the street level and they are
incapable Of approaching its dimensions
from the measurements glibly rolled out by
the guide or given in the cold type of a
guide book.
Mention of 2l11-foot dial. with two-foot-
high numerals. and hour and minute hands
nine feet and sixteen feet long respectively.
conveys little to the mind until one is
brought face to face with these component
parts on an equal level: then the eyebrows
rise with establishment as one appreciates
for the first time the actual size of a giant
clock.
Take for example. the dial plan for a
Big Ben made for Toronto. Canada. Men
beside 1t look like Lilliputians. and 1T would
take four of them, standing on one an
others shoulders. to equal its height for
it has a diameter of twenty feet. Its min
ute hand is the height of two men, while
the hour hand is five feet IN length.
Then the numerals have 4 height of two
feet nine inches. and the minute strokes
are just half foot in length. In perform
ing its daily task of indicating the time,
the long hand in this clock. which now an
nounces the hour to the good people OF
Canada from the height of the town hall
tower travels a quarter OF a mile. or nine
ty-one and one-quarter miles year!
The first consideration in the making of a
huge clock is the meteorological conditions
under which 1t will have to perform the
duty required of it, AS an instance. take
the case of the clock that was constructed
by this firm for Toronto The hands do
their work at an elevation of go feet, and.
snowStorm or no. complete their daily
round without resting. With hands not
specially built TO resist it, Canadian snow
storm would do surprising things. even to
twisting them and breaking them off.
Ordinarily the hands of turret clock
are cut out of sheet copper. stiffened with
ribs of brass a the back. Were this not
done the wind would blow them out of tuth.
But where they have to work under such
conditions the Toronto time piece they
are formed elliptical in shape of double
sheets OF copper convexed toward the cen
ter, and strongly riveted every four inches
of their length.
After the planning of the dial the tenn
plet from which the mold is made has to
be cut. and the great dial is cast whole in
iron The huge frames to contain the in
tricate and delicate mechanism of the
works are likewise cast in one piece. Re
memberng that the clocks are exposed to
the changing conditions of weather. and
the influences of those conditions on meta l.,
the necessity of dispensing with nuts,
screws and bolts becomes apparent.
The giant dials vary from eighteen to
sixty feet in circumference and the dial
room at a makers of tower clocks is an
interesting sight. There are dials. mostly
skeletons, of iron, in various stages toward
completion all around. being painted and
glazed and gilded. Those intended to serve
in Illuminated clocks are glazed with opal
glass. this. better than any other. diff
fuses light equally over the surface of the
dial. But Skeleton" diaIs, intended for a
tower whose wall will be the only back
ground to the iron casting between the hour
and minute spaces. are generally gilded.
According to their size. they vary in thick
ness and weight. Such one as the Toron-
to dial completed would not weigh much
under four tons.
With the making of the actual works
there is not space to deal here, and a des-
cription of them would only puzzle the lay
mind. They are mass of complicated but
delicate machinery, and constitute a ver-
liable marvel of mechanical construction.
OF course. no tower clock would be COM
plete without its bells. and though the COM
ponent parts OF the metal from which these
cast are no secret. their making calls
for much Judgment and skill. There must,
of course. be the proper proportions Of tin
and copper, the scientific mixing Of them
in the furnace, and one must know the
exact moment to run the metal into the
mold. after the cores. from which the
bells are shaped, have been built up and
dried.
Then there is the tuning of them. To tune
bell is declared to be most difficult bust
ness because when struck 1t sounds a trio
of notes instead of one. Consequently. 1t
requires expert ear to catch the domi-
nant note. By special machine, the in
vention of the firm in question. this difficult
ty has been largely overcome, and the oper-
alton of tuning much simplified
BY the aid Of this clever ,contrivance tho
tuning can be accomplished gradually
that the variations of the note are only
distinguishable to the trained ear.
The bell is inverted. 1t Is held stationary
by powerful vises, the steel cutters for par
Ing the metal to secure the required note
being In the interior. These cutters are
revolved by machinery. and shave the metal
as easily as plane shaves a deal plank.
In this manner the bell Is toned, either up
or down. desired, till the correct note
Is secured
Some Of the pendulum "bobs'' weigh as
much as four hundredweight. while the
weights that furnish the power to make
1.-The wheels go around require the united
efforts of a couple of men to raise them.
Both these parts. together with the ire
mendous hammers for announcing the
flight of time. are cast In the foundry
From this 1t will be gathered that the
building of a giant clock Is no light labor.
1t calls for the combination Of scores OF
pairs of hands, and the workmen must all
be experts at their particular branch OF
the business, from the humblest painter OF
dials TO him who builds up the innumerabls