Only Online Auction

Geneva, Apr 07, 2021

LOT 267

Société Genevoise pour la construction d’Instruments de Physique (SIP)
Horological miscellaneous; demonstration model of a differential gear; cast iron, brass and wood

CHF 3,000 - 5,000

EUR 2,800 - 4,600 / USD 3,300 - 5,400 / HKD 25,200 - 41,900


Sold: CHF 2,250

Cast iron and brass, demonstration model of a differential gear with dials and indexes, probably built to demonstrate an indication of power reserve; on a wooden base.

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Grading System
Grade: A


Case: 3-6-8


Slightly oxidized

Slightly scratched

Brand SIP, Geneva

Year early-20th century

Material cast iron, brass and wood

Length 175 mm.

Dimensions (approx.)

Height 350 mm.

Width 300 mm.


The Société Genevoise pour la construction d’Instruments de Physique (SIP)

The company was founded in 1862 by Geneva scientists Auguste De la Rive (1801-1873) and Marc Thury (1822-1905) to manufacture scientific instruments. From 1870, under the impetus of Théodore Turrettini (1845-1916), it diversified its activities into new energy sectors (hydro-motors, refrigeration systems, electricity meters), as well as metrology (precision rules). This three-fold expertise led to the development, in 1921, of a machine tool that would contribute to the growth of mass production in mechanics, the pointing machine, called the “MP”, capable of machining with a precision of the order of a thousandth of a millimetre. A true technological feat, this production will make SIP one of the most prestigious machine manufacturers in the world. After employing up to 1 600 people (1969), a prisoner of its engineering culture, the company struggled to adapt to the economic changes that affected the industry from 1970 onwards. In 1990, SIP left its Plainpalais site for Satigny. In 2006, with only around 40 employees left, it was taken over by the StarragHeckert group.


The purchase price payable by a buyer will be the sum of the final bid price plus the buyer’s premium, together with any applicable sales or compensating use tax. In addition to the hammer price, the buyer’s premium is payable as follows: 25% of the hammer price on each lot.

Important notice – Special conditions Please look carefully at all the photos as they are an integral part of the description. Any defect not mentioned in the descriptions but visible on the photos will be considered as described and cannot lead to any claim. The dimensions are given as an indication and may slightly differ from the measures mentioned by the manufacturers especially for contemporary watches. The photos are not retouched. Colors may differ from reality. For timepieces, we guarantee neither the functioning nor the precision of the movement, nor the water-resistance of the case. In addition, please note that movements, parts of mechanisms or cases may be incomplete. The lots are sold “as is”, described to the best of our knowledge and cannot be returned. Once the online bid is placed by the bidder, it cannot be cancelled.