103rd Auction

2020/11/7

Lot 88

Sigmund Riefler, München, DRP No. 50739 / 1008740, Movement No. 56, Height 1370 mm, circa 1900
An important, astronomical tank precision regulator - Type D - with Riefler spring impulse escapement and Winbauer's electrical winding sold to the observatory of the "Case School of Applied Science" in Cleveland - in nearly the same condition as at the time of first delivery, with original glass tank and bell jar, barometer, thermometer and hygrometer, extra weights and tin of Vaseline for sealing purposes
Case: air pressure constant glass tank with glass dome, cast-iron wall bracket. Dial: silvered. Movm.: rectangular-shaped brass movement, seconds contact device, spring impulse escapement no. 73, invar steel pendulum "type J¹", no. 28, DRP no. 100870.
"The most accurate clock in the world"
Among the precision pendulum clocks made by the Riefler company are quite a few that attract attention because of their history, the site of their installation or even their owners; some of them were awarded special honours, some were in service at important institutions, others had illustrious owners such as the Pope, who used one of the clocks in his observatory.
Clock No. 56, however, gained particular fame very soon after its installation – it was sent to Cleveland in Ohio on April 23, 1901. It is worth noting that in the early days of his business, Riefler delivered almost as many clocks to the U.S. as to Germany; Riefler was not only a gifted engineer but also a very active salesman who early on discovered the market niche generated by the introduction of standard time (among other things). It was in particular the exhibition at the World's Columbian Exposition, the world’s fair in Chicago in 1893 that made Riefler’s precision clocks popular in the U.S. and ensured that some of the very early clocks were sold to American institutions: No. 6 and 36 to Washington, No. 7 to Philadelphia, No. 35 to Providence, No. 65 to Harvard University and No. 88 to Albany, NY. Clock No. 76 was set up in Washington and delivered American standard time from 1904 to 1929.
After our No. 56 had been operating for about a year at normal conditions at the "Warner and Swasey Observatory" in Cleveland, local professor Charles S. Howe described his experience with the clock in an article for the "Astronomical Journal" in 1992. He describes first the optimal air pressure and temperature conditions that are needed for accurate operation of the clocks; he then concludes that only the tank clocks made by the Riefler company are up to the standard. The evaluation of the test results and comparisons with clocks at other institutions lead him to believe that their values are "better than any other published observations".
In an essay on the "historical development of technology in Southern Bavaria", Paul v. Lossow picks up on the topic and writes: "From the test results of these clocks, which are available from different observatories, it is the table last published by Professor Howe in the Astronomical Journal No. 524 on August 11, 1902 with the results of the Riefler clock No. 56 in service at the Cleveland, Ohio observatory that should be mentioned here, with hermetically sealed interior, nickel steel pendulum and electric winding. According to the results, the clock is accurate to a mean of 0,015 seconds per day and the largest deviation measured over several months is 0,022 seconds. These are the bests results we know from any clock so far; it should be taken into consideration that these are directly recorded results which have not been converted in any way with regard to amplitude, temperature etc.."
Other authors also discussed this clock; Willis I. Milham describes it in his book "Time & Timekeepers" and a doctoral thesis was written on it at Case Western Reserve University, which today includes the former Case School of Applied Science. Riefler’s sales book proudly records: "Als beste Uhr der Welt bezeichnet! Tagl. Var. ± 0,008s" (Described as best clock in the world! Accurate to ± 0,008 seconds per day).
Since the clock was retired from the observatory it has been privately owned and never been offered for sale. The clock has never experienced any major damage and is in many respects in nearly the same condition as at the time of the original sale in 1901: The glass tank and the bell jar are original and whole, the original measuring instruments are present (the barometer that was damaged during delivery was replaced immediately in 1901 before the clock was put into service); there are extra weights in the original small Riefler box and even the tiny tin of Vaseline to seal the rim of the glass seems to have been part of the original delivery, as it comes from the "Stern"pharmacy in Munich. Only the pump used to create the vacuum is an American model.
Even without its history and without looking at its excellent condition this Riefler clock is an exceptional rarity for collectors: There were altogether only 49 type D clocks with glass cylinders and some of them are known to be damaged or even destroyed; of the early clocks with the Winbauer winding system only seven were ever built before Riefer began using his own patented system.
The Riefler company was always relentless in the pursuit of their goal - to build the most accurate clocks in the world. The three type E clocks were accurate to approximately one second every four years and in the early 1960s when they were built, this was "top of the line" for mechanical clocks. It was, however, even then starting to become clear that atomic clocks were to be the clocks that rule our world.

Sold

estimated
80.000150.000 €
Price realized
184.000 €