Clocks,
Watches, Music Boxes 1
Clocks, watches, musical boxes
In the first instance clocks were made to be placed
prominently in outdoor positions to tell the time
to the people at large. In due course, smaller examples
were made for use in the home, and eventually a further
reduction in size led to the introduction of the
personal pocket-watch.
The earliest clocks with movements driven by the
power from a falling weight had neither hands nor
dial, and marked the hours by striking a bell. Eventually,
a face to show the hours was added, and at a later
date the hours were divided into minutes and a further
hand affixed to indicate them. These clocks were
heavy iron-framed affairs, usually placed high inside
a tower within which the weight had a good distance
to travel before it needed rewinding.
Regulation to prevent the weight crashing down from
top to bottom of the tower was achieved by a device
known as a Foliot balance. In this, the final wheel
in the train was set on a horizontal spindle.
The wheel, called the crown wheel because of its
appearance, was cut with comparatively long angled
teeth into which fitted alternately two flat plates
(or pallets) on an upright spindle. At the top of
this latter spindle was a shaped arm with adjustable
weights at either end for regulating the speed of
the clock. For smaller indoor clocks the swinging
arm was replaced by a wheel, and the speed was controlled
by making the weight lighter or heavier.
Early in the sixteenth century appeared the first
clocks using a coiled spring instead of a weight.
The fact that the power exerted by a spring grows
less as it uncoils was the subject of much research,
and a device known as the fusee was the successful
outcome. It takes the form of a cone-shaped drum
with grooves on to which the gut or chain from the
mainspring drum is wound. As the spring is uncoiled
it reaches the larger circumference and this equalizes
the weakened pull. The use of springs and fusees
encouraged the making of portable clocks and these,
first made in Germany, soon became popular. Their
time-keeping, like that of all other clocks, was
erratic and the sundial remained an essential standby.

Fig. 8. The Foliot.
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Antique
Clocks
The use of springs and fusees encouraged the making
of portable clocks and these, first made in Germany,
soon became popular. Their time-keeping, like that
of all other clocks, was erratic and the sundial
remained an essential standby.
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