Neon advertising signs brought a vintage glow to Bright Star and W. Yoder

International Harvester double-sided neon sign, which sold for $14,000 ($18,060 with buyer’s premium) at Bright Star.

SULPHUR SPRINGS, TX AND WAUTOMA, WI — Antique neon advertising signs continue to command top dollar from collectors, as demonstrated at two LiveAuctioneers-affiliated houses recently.

Bright Star Antiques Co. offered what appeared to be a 1950s-era porcelain and neon sign for International Harvester on May 4. The ‘man on tractor’ stylized I and H had been designed in the immediate postwar period, but was not fully rolled out until 1953 as the reigning corporate logo. The neon-enhanced sign measures 51.25 by 46.25in and is double-sided for use as either a hanging or a pole-mounted installation. Estimated generally at $50-$1,000, it took only two LiveAuctioneers bids for it to hammer at an astounding $14,000 ($18,060 with buyer’s premium).

Likely from a retired or scrapped GMC SceniCruiser (the so-called ‘two-story’ buses) is a Greyhound Bus Lines lithographed-tin dog sign ringed by contemporary neon in two colors. Massively large at 8ft by 3ft, the original Greyhound signs distinguished the vintage buses. Estimated at $50-$2,000 by auctioneer W. Yoder in its May 3 auction, the sign sold for $6,250 ($7,812 with buyer’s premium).

In the same sale, Yoder also offered a one-sided wall-mount steel and neon Greyhound Bus ‘Depot’ sign featuring the bus company’s trademark dog logo. It hammered for $5,000 ($6,150 with buyer’s premium). Measuring 52 by 31.5in, it carried the markings of its manufacturer: The Carey Mfg Co., Charleston W. Va.

Six mystery clocks, one of each type Robert-Houdin made, appear together at Potter & Potter June 8

Robert-Houdin Triple mystery clock, estimated at $50,000-$70,000 at Potter & Potter.

CHICAGO – Examples of all six of the mystery clocks created by Jean-Eugène Robert-Houdin (1805-71) come for sale at Potter & Potter Auctions on June 8. A total of six clocks by the 19th century French magician and horologist form part of the personal collection of dealer and seeker of the unusual Peter Hackhofer.

The genius that was Jean Eugene Robert-Houdin began to develop the very first mystery clocks around 1830. As discussed by Derek Roberts in Mystery, Novelty & Fantasy Clocks, Houdin produced six distinct types of mystery clock at his workshop in Blois, all operating with no visible connection between the hands and the mechanism.

Many speculated these were driven by the relatively new science of electromagnetism. In fact, all used optical tricks to conceal twin-train striking movements. Each model took the illusion further.

Robert-Houdin’s first mystery clock, an instant success when first exhibited in London and Paris in the 1830s, was titled La Fleur Mysterieuse. With an enamel circular dial creating the illusion of a clock working without power was relatively simple. The example here, with its mechanism cleverly concealed within a patinated bronze support modelled as a griffin, has a guide of $12,000-$18,000.

Later developments were more complex. Viewers were left to guess at how the hands of a clock could turn and kept good time when the dial was made of clear glass. They worked via the ingenious rotation of a glass sheet and a toothed rim to move the hands.

A Series 2 clock circa 1835-1840 with a single hand to the glass dial is estimated at $15,000-$25,000 while a Series 3 clock circa 1840-1845 with its dial supported by a clear glass tube is expected to bring $30,000-$40,000.

As the name suggests, Robert-Houdin’s Series 4 or triple mystery clock contains three puzzles: a glass dial with two arrow-shaped hands apparently moving independently; a glass pillar with no means of transmitting propulsion and, finally, no apparent connection between the gears in the pedestal and the clock itself. Peter Hackhofer owned a particularly fine example dated circa 1850 that is estimated at $50,000-$70,000.

Robert-Houdin thought his circular dial clocks were losing their allure and developed the square-dial model which works by using several layers of glass to the dial and minute oscillations produced by a cam and rod. There are two versions of this model (Series 5 and Series 6) that are guided at $20,000-$30,000 each.