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Lot Essay
Two Riefler regulators of related design with type 'J' pendulums have appeared at auction recently, both slightly later models: No. 431, Bonhams London, 14 July 2010, lot 143 (£43,200) and No. 398, Christie's London, 23 September 2010, lot 123 (£32,450).
Clemens Riefler (1820-1876) was a successful drawing instrument and pendulum clock maker who established the family firm named after him. Derek Roberts writes (Precision Pendulum Clocks: France, Germany, America and Recent Advancements, Atglen, 2004, pp. 119-121) that when Clemens died his sons, Theodore (1853-1931) and Adolf (1850-1909), took over the technical, sales and management sides of the business whilst another son, Sigmund (1849-1912), a gifted horologist from a young age, worked on developing compasses and precision clocks. By 1877 Sigmund had designed a new compass system, called the Rund (round) System, which proved a great success, so much so that the company had to move to larger premises in Nesselwang, where it continues today.
In July 1889 Sigmund patented his first free pendulum clock escapement (DRP No. 50739), which he considered it to be as near theoretically perfect as possible. In March 1891 he obtained a further patent (DRP No. 60059), for a mercury pendulum, and later that year sent his first regulator to the university observatory in Munich-Bogenhausen. Riefler exhibited at the 1893 World Exhibition in Chicago and gained first place in a competition for inventors in horology. The following year Riefler was awarded the John Scott Medal of the Franklin Institute, Philadelphia, and by 1894 Sigmund was appointed to the Committee of the Polytechnic Association in Munich. He went on to design and produce regulators in air-tight tanks which gave a guaranteed rate of +/- 0.008 seconds per day and thus beginning a new era in the accuracy of regulators. In 1897 Sigmund was granted the degree of Dr. Phil. H. d. by the University of Munich for his pioneering achievements in the field of time measurement.
In 1887 Sigmund Riefler was one of the first clockmakers to utilize Professor Guillaume's newly discovered alloy, invar, which had a very low coefficient of expansion. That is to say, given a change in temperature, the length of an invar pendulum will alter significantly less than one of plain steel; it will therefore keep more constant timekeeping across a range of temperature changes. Sigmund developed a special treatment to make this new material stable and designed a pendulum which he subsequently patented (DRP No. 100870). The development of his pendulum continued until production ceased in 1965 by which time over 3,600 had been produced, the majority of which were sold to other clock makers.
Clemens Riefler (1820-1876) was a successful drawing instrument and pendulum clock maker who established the family firm named after him. Derek Roberts writes (Precision Pendulum Clocks: France, Germany, America and Recent Advancements, Atglen, 2004, pp. 119-121) that when Clemens died his sons, Theodore (1853-1931) and Adolf (1850-1909), took over the technical, sales and management sides of the business whilst another son, Sigmund (1849-1912), a gifted horologist from a young age, worked on developing compasses and precision clocks. By 1877 Sigmund had designed a new compass system, called the Rund (round) System, which proved a great success, so much so that the company had to move to larger premises in Nesselwang, where it continues today.
In July 1889 Sigmund patented his first free pendulum clock escapement (DRP No. 50739), which he considered it to be as near theoretically perfect as possible. In March 1891 he obtained a further patent (DRP No. 60059), for a mercury pendulum, and later that year sent his first regulator to the university observatory in Munich-Bogenhausen. Riefler exhibited at the 1893 World Exhibition in Chicago and gained first place in a competition for inventors in horology. The following year Riefler was awarded the John Scott Medal of the Franklin Institute, Philadelphia, and by 1894 Sigmund was appointed to the Committee of the Polytechnic Association in Munich. He went on to design and produce regulators in air-tight tanks which gave a guaranteed rate of +/- 0.008 seconds per day and thus beginning a new era in the accuracy of regulators. In 1897 Sigmund was granted the degree of Dr. Phil. H. d. by the University of Munich for his pioneering achievements in the field of time measurement.
In 1887 Sigmund Riefler was one of the first clockmakers to utilize Professor Guillaume's newly discovered alloy, invar, which had a very low coefficient of expansion. That is to say, given a change in temperature, the length of an invar pendulum will alter significantly less than one of plain steel; it will therefore keep more constant timekeeping across a range of temperature changes. Sigmund developed a special treatment to make this new material stable and designed a pendulum which he subsequently patented (DRP No. 100870). The development of his pendulum continued until production ceased in 1965 by which time over 3,600 had been produced, the majority of which were sold to other clock makers.