Antique
Clocks
Humankind
has always recognized the passing of time and has tried
to measure and record that passing. The simple alarm clock
at your bedside table owes its existence to more than 6,000
years of thinking about time and tinkering with devices
to accurately mark its passage.
A
general knowledge of time division was relevant to the earliest
of farmers, who sectioned quadrants of time into broad periods
of seasons for planting, growing and harvesting. In those
days however, the actual hour of any particular day was
not important.
As
early civilizations grew and became more complex in their
needs for order and governance a more precise measure of
time was required. The early Egyptians originated the division
of each day into two measurable parts, using the position
of an obelisks shadow to mark high noon. Other early and
more precise timekeeping devices also include the hourglass,
indexed candles that burned at a fixed rate, and water powered
devices.
Early
Mechanical Clocks
In
medieval times, the regulation of monastic calls to prayer
was accomplished by means of mechanical tower clocks. This
revolutionary device soon synchronized the rhythms of entire
cities. World views of entire cultures were influenced by
the type of clocks they used. The development of atomic
clocks, accurate to a billionth of a second, seem to reflect
modern society's near-obsession with youth, age and the
passage of time.
The
very first early mechanical clocks, which didn’t have
pendulums, were developed in the last half of the thirteenth
century, probably by monks from central Europe, and were
placed within the church. They did not have dials or hands
and only struck bells on the hour. These mechanical devices
were probably placed in the church belfry in order to make
use of the existing church bell. It was over 100 years before
visible dials and hands were added. These early clocks were
very large and were made of heavy iron frames and gears
forged by the local blacksmiths.
In
1580 or so, the Astronomer Galileo observed a swinging lamp
suspended by a long chain from a cathedral ceiling. He studied
its swing and discovered that each swing was equal and had
a natural rate of motion. He later found this rate of motion
depended upon the length of the chain or pendulum. Many
years later in 1640 he designed a clock mechanism incorporating
the swing of a pendulum, but he died before building his
clock design. Later in 1656 Christian Huygens added a pendulum
to a clock mechanism of his own design and found it kept
excellent time. Regulating the speed of the movement was
done, as it is today, by simply raising or lowering the
pendulum bob-up to speed-up the clock, down to slow-down
the clock-thus the terms “speed-up;’ “slow-down.”
Note: the length of a pendulum is usually considered to
be the length from the center of the shaft that holds the
hands to the center of the pendulum bob (some-times it is
from the center of the shaft that holds the hands to the
bottom tip of the pendulum bob).
Huygens
invention allowed clocks to be accurate to as little as
three minutes loss or gain per day instead of the previous
quarter to half an hour per day variance. The introduction
of minute hands resulted from this increased accuracy. By
1670, with the introduction of the anchor escapement, decreased
the time various to as little as a few seconds per week.
By
the first part of the fifteenth century, small domestic
clocks started to appear. They were probably made by the
local gunsmiths or locksmiths. After1630, a weight-driven
lantern clock became popular for the home use of the very
wealthy. When the swinging pendulum was added in 1656, clocks
became more accurate. Very early clock movements were mounted
high above the floor because they required long pendulums
and large cast-iron descending weights. In reality, they
were nothing more than simple mechanical works with a face
and hands. They were referred to as “wags-on-the-wall”
The long-case, or grandfather clock actually evolved from
these early wags-on-the-wall prototypes. Wooden cases were
used only to hide the unsightly weights and cast-iron pendulum.
Although
the Dutchman Hyugens’ innovative pendulum design brought
a great leap forward in clockmaking, it was English clockmakers
who reigned supreme in Europe from about 1660 to the early
19th century American introduction of inexpensive brass
movements. |