Aaron Crane Torsion Pendulum Clock

Aaron Crane Torsion Pendulum Clock

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Aaron D. Crane (1804-1860) of Caldwell, New Jersey, was a clockmaker of brilliant inventiveness who worked outside the mainstream. Most of his contemporaries concentrated their energies on the mass production of technically unremarkable clocks. Crane was a versatile inventor whose best-known work, the torsion pendulum clock (patented in 1841), was startlingly original. This clock employed a torsion pendulum, slowly revolving about the vertical axis in alternating directions, and incorporated a new escapement of Crane's own design. It worked with such freedom of friction that it was capable of running for extremely long periods. Crane advertised his clocks as "month clocks," "twelve-month clocks," and "376-day clocks." He liked to refer to himself as the "One Year Clockmaker."
He installed most of his torsion pendulum clocks in unpretentious, rectangular cases, but in the last decade of his life he built a few clocks based on the ornate design of this one. Five survive.
In addition to telling time, this clock has a dial marked "astronomical" that indicates the day of the year, the position of the sun in the zodiac, the phase of the moon, the length of day and night, and the time of the tides.
Besides his clocks, Crane tried to market a variety of inventions through a number of businesses in Newark, New York City, and Boston. For all his mechanical ingenuity, he had little commercial success.
Some twenty years after his death, the torsion pendulum clock was reinvented independently in Germany and marketed as a "400-day clock" or "anniversary clock."
Currently not on view
Object Name
Date made
ca 1850
Crane, Aaron
Place Made
United States: New Jersey, Newark
Physical Description
marble (overall material)
brass (overall material)
overall: 21 in x 11 in x 5 in; 53.34 cm x 27.94 cm x 12.7 cm
ID Number
catalog number
accession number
See more items in
Work and Industry: Mechanisms
Industry & Manufacturing
Data Source
National Museum of American History
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