Winning Bid: $30,000
An early 20th century type D observatory tank regulator signed S. Riefler:
Sigmund Riefler, Munich, an early 20th century type D observatory tank regulator, the jeweled, type A movement with spring impulse escapement, electric remontoire, knife edge suspension resting on polished agate pads, and a 60 tooth wheel mounted to the escape arbor, with switch for sending signals at one second intervals, the silvered astronomical dial with blued steel hands and engraved “S. Riefler Munchen No. 150 1905”, type J1 seconds beating pendulum with invar rod and cylindrical bob, serial #730, all contained within a copper cylinder covered with a bell jar, and suspended by a heavy cast iron bracket, with control panel. This clock was originally installed at the Royal Observatory, Cape of Good Hope (now Capetown), South Africa.
tank with scratches, tank plugged at original location of vacuum valve, tank fitted with six terminals, bell jar with rim chip, clock mounting frame with losses to gilding, dial with minor dirt, hands good, top of contact adjusting screw with solder, movement good, pendulum bob with small spot of corrosion, iron bracket now painted green and with white paint speckle, lacking microscope. Sigmund Riefler (8/9/1849 – 10/21/1912) was the son of Clemens and Magdalena Riefler, and was responsible for the advancements that brought the Riefler firm to the forefront of precision timekeeping. His innovations include the spring impulse escapement, which isolated the pendulum from direct contact with the escapement and provided a more equal impulse, a scientific and mathematical approach to the improvement of compensated pendulums, which reduced the reliance on an empirical, inexact approach to the refinement of design, and finally, his electric remontoire, which eliminated the need for much of the wheelwork, with a resultant reduction in friction and irregularities in power transmission to the escapement. Riefler’s late 19th century regulators significantly improved the accuracy of the pendulum clock, and became the standard for observatory use until surpassed by the Shortt – Synchronome free pendulum clock, c1920. ACCESSORIES: Bell Jar, Tank, Iron Bracket, Miscellaneous Screws Etc., Control Panel, Movement, Pendulum Rod, Pendulum Bob, 53.5in x 15in x 14.5in