Patek Philippe

• cal. 17-250É photo-electric movement, Gyromax balance, 29 jewels, adjusted to heat, cold, isochronism and one position • silvered dial, painted elongated baton indexes radiating from an eccentric point, apertures for digital displays of day, date and month • gilt-brass rectangular case with engraved inscription to the back, solar panel to the top • movement signed by maker, dial signed by maker and retailer

The clock is wonderful and very rare. The mechanical movement appears to function, when tension is put on the wheels when the hands are changed, however it does not run as there is no battery to power the winding motor. The old battery appears to have leaked to the inside base and the inside of the back cover of the clock. The calendar corrector levers appear to function properly. The case shows signs of wear and spots where the gilding has come off, particularly to the outside of the back. The engraved presentation inscription to the back reads: 'Presented to Austin Stanley Moscowitz, "A Friend Who Always Has Time For His Friends". Dan Berley, David Berley, Herman Leffler, Harold Lieberman, Ben Lieberman, Harry Sadel, Luke Sapan, Bob Schwartz, Paul Steiner, January 30, 1969'. The dial is very nice with no major marks. Please note that the piece is further accompanied by an Extract from the Archives confirming production in 1967 and sale on March 19th, 1968.
"This lot is offered for sale subject to Sotheby's Conditions of Business, which are available on request and printed in Sotheby's sale catalogues. The independent reports contained in this document are provided for prospective bidders' information only and without warranty by Sotheby's or the Seller."

Accompanied by an Extract from the Archive confirming production in 1967 and sale on March 19th, 1968. Togethar with a Patek Philippe Instruction Guide, a calendar adjustment diagram and a facsimile of a promotional brochure for photo-electric clocks. Further accompanied by a Patek Philippe inner presentation box and Tiffany & Co. outer packaging and cloth pouch. It is interesting to note that the accompanying letter from Tiffany & Co. promises the client a 'lifetime guarantee' for the piece.

Patek Philippe began developing photo-electric technology before 1950, and at the time, harnessing light to produce energy was cutting edge technology. Solar technology had not yet diffused into a wide range of products. The novelty was such that in promotional literature for the clocks from the 1960s, Patek Philippe's frame of reference were the solar panels used to provide energy for the cameras aboard NASA's robotic Surveyor spacecrafts.

The result of seven years of research and development, Patek Philippe's photo-electric clock was not only among the first civilian uses of solar power, but the first application of this technology in any horological piece. It was also the first freestanding, portable timepiece operated by means other than a traditional mechanical movement. Along with the advent of the electromechanical and quartz movements, this solar-powered milestone was one of several significant advances in the third quarter of the 20th century that threatened to render mechanical movements obsolete.

The photo-electric movement on the present example functions by a combination of several different mechanical processes. The upper solar panel collects artificial or natural light, which is transmitted via wires to a battery. This energy is then used to adjust the calendar wheels and wind the mechanical cal. 17-250É movement.

This movement is particularly interesting for its allusions to Patek Philippe's more traditional work. Cal 17-250É is a variation of the watch movement cal. 17-250, and is distinguished by three major differences. The first is that cal. 17-250É is rendered in gilt metal rather than nickel-finished metal. Secondly, the wheels of the gear train on the present example are noticeably larger than they would be in a watch movement. Third, and most interestingly, is in the layout. Cal. 17-250É features a gear train that has been separated from and housed adjacent to the main movement plate. This unusual configuration places the wheels directly in front of the torque device that acts as a winding mechanism.

This unusual and highly inventive movement yielded impressive results: the accompanying brochure for the piece notes that the clock will be accurate up to one second each day, and that the clock could potentially function indefinitely with four hours of dim artificial light per day, or for a year in complete darkness.