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    Hamilton Permanent Magnet Model 1 Mark 4, One Of Four Prototypes, René Rondeau Collection
    PM-1, Mark 4, one of four PM prototypes which would eventually evolve into the Hamilton 500. Movement only, incomplete, (as are all PM-1 prototypes - no gear train was used). With
    original patent from Hamilton archives, dated August 9, 1960 and issued to John Van Horn, Philip Biemiller, and James Reese. (PM-1, Mark 1 is in the Smithsonian.)

    The team of Van Horn, Reese and Biemiller began construction of a working model in July, 1952. In this watch, known as the "Model 1" of PM-1, the sides of the movement consisted of two curved magnets made of Alnico 5, a common and powerful magnetic alloy. The center of the movement was entirely taken up by a large balance wheel shaped like a figure-eight, wrapped tightly in fine copper wire to form the coil. The rare example presented here is featured in "The Watch of the Future" on page 33.

    Condition Report*: Type: Hamilton Permanent Magnet Model 1 Mark 4, One Of Four Prototypes, René Rondeau Collection
    *Heritage Auctions strongly encourages in-person inspection of items by the bidder. Statements by Heritage regarding the condition of objects are for guidance only and should not be relied upon as statements of fact, and do not constitute a representation, warranty, or assumption of liability by Heritage. All lots offered are sold "AS IS".

    Auction Info

    Auction Dates
    October, 2015
    29th Thursday
    Bids + Registered Phone Bidders: 3
    Lot Tracking Activity: N/A
    Page Views: 921

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