Ca. Ø56mm, ca. 143g, 18K gold à-goutte, back with elaborate monogram, signed and numbered dome, extremely rare Ankerchronometer movement with experimental chronograph, extremely rare quality, diamond endstone, plate signed and inscribed 'Inventeur', the original enamel dial as well, pink gold hands, in working order, in good condition with original signed box, absolute rarity. Only a few of these watches are known. To use the chronograph, the lever at 11 is pushed counter clockwise while the button is pressed. Releasing the pusher stops the chronograph. The absence of an additional pusher reduces the time required to stop. The zero setting is done by pressing down the winding crown. Rötig was a watch and chronometer maker based in Le Havre. He advertised his watches with the title 'Constructeur de Chronomètres' and 'Inventeur'. He was also 'Horloger de la Marine' in Le Havre. We know of only one example of these experimental chronographs that was sold at auction: No.1635, auctioned for 12,600CHF in 2004 (source: https://www.cortrie.de/go/DPd).