Johnstown weekly Democrat. (Johnstown, Cambria County, Pa.) 1889-1916, 1890-06-27
AN INTERESTING CLOCK.
ITS Maker Is Proud of 1t. but He Has No
Wish to Make Another.

In the window Of German jeweler
on Court street, Brooklyn, there stands
brass clock not more than ten inches
high. The passerby who looks through
the window sees under the clock, which
is supported by four polished columns,
a small brass platform, balanced to
nicely ON two pivots in the middle, like
an ordinary seesaw. A groove cut into
the surface of the brass runs zigzag
from one end to the other, and on the
path so made brightly polished steel
ball, no larger than bullet runs un-
ceasingly. When the ball has Travelled
from one end of the platform to the
other, zigzagging from side to side, it
strikes thin steel wire which hangs
from above, and in an instant the plat
form is tilted up at that end and the little
ball, ilnpelled by the force of gravity,
starts back again. At the other end it
comes into contact with another wire,
and up goes the platform once more.
Sometimes big crowd stand around
the window intent on the little sphere,
the mystery of which they find it hard to
solve.
f. 7. Kraft, who runs the store, has
followed his trade for many years. One
day six years ago Kraft was walking
down Broadway when he saw a clock in
a jewelers. window with the same de-
vice. He stood for an hour in front of
the glass watching it and trying to solve
the problem of its construction. The
proprietor of the store told him the clock
had been made in England twenty-five
years before, and was the only one of its
kind in existence Mr.. Kraft's request
to have look at the mechanism was
met with refusal, and he went off with
the determination to study it out for
himself. He worked at it six months
during his odd hours and finally tri-
umphed. Then he was surprised to find
how simple the idea was after all, al
though he found the greatest deicacy
necessary in carrying it out.
Mr.. Kraft took the clock from its shelf
in the window to explain its mechanism
to the reporter. The two mysterious
wires which the ball strikes against at
the end of each trip are fastened above
TO long rod. From the upper side of
this rod runs a strip of steel which rests
against one of four pins on an escape
ment wheel in the works When the
ball strikes the wire it releases this
wheel, which makes a quarter revolution
to the next pin. On the same axis is a
cog wheel whose teeth fit into those of
another of half the circumference. The
smaller wheel makes a half revolution
while the other is making quarter. To
the axis of this wheel is fastened rod,
which is attached at its other end to the
platform, which is pulled mp or down ac-
cording to the wire which the ball
strikes.
1t was in the manufacture of the ball
itself that Mr.. Kraft had the most diff
Guilty. 1t had to be u perfect sphere to
work properly, and it was turned down
bit by bit to the proper size. A little
guard rail is placed at each angle of the
groove, so that the ball will not jump
off. 1t takes the ball just five seconds
to make the trip, half second for each
section of the groove. The platform acts
as a pendulum with a five second swing,
The device is only interesting as novel.
ty, as it is more susceptible to changes
in the weather than the pendulum clock,
and has to be regulated frequently.
It is interesting to figure out the dis
tance which the Industrious little ball
travels from day to day. Every second
it runs 20 inches, or % feet minute.
This il quarter of mile an hour, or
miles Il day, or 190 miles a month, or
21 ,79O miles year, over II, ,O00,0 feet
Since the clock was first started the
ball has travelled a distance equal to
nearly three-fourths of the way around
the globe In that time it has not been
worn toa any perceptble degree, although
the brass surface on which it runs has
been ground oil considerably.
Il have had lots Of offers for this
clock" said the old ieweler, as he put it
back on its shelf, "but l wouldn't sell it
for any price Itwas pleasure to work
out the principle Of the thing, but you
couldn't get me to make another one of
them for a good deal. New York Sun.