Important Collectors' Wristwtches, Po...

New York, Sep 26, 2007

LOT 181

?1911 BTR Perpetual Chronograph? Ebel, ?1911 BTR Perpetual Calendar Chronograph?, No. 15/20. Made in a limited edition of 20 pieces in 2006. Fine and rare, tonneau-shaped, self-winding, water-resistant, stainless steel wristwatch with round-button chronograph, perpetual calendar, moon phases, tachometer and a stainless steel link bracelet with deployant clasp. Accompanied by a fitted box and certificate.

USD 7,500 - 9,500

EUR 5,600 - 7,000

Sold: USD 9,676

C. Three-body, solid, polished and brushed, bezel with 5 screws, concave lugs, transparent case back, screwed-down octagonal winding-crown, sapphire crystals. D. Matte silver with applied luminous steel baton markers, subsidiary dials for the 12-hour and 30-minute registers, the days of the month, of the week, the months and the leap year, outer tachometer graduation, aperture for the moon phases. Steel "baton" hands. M. Cal. E 288, rhodium-plated, ?fausses côtes? and "oeil-de-perdrix" decoration, 27 jewels, straight line lever escapement, monometallic balance, shockabsorber, self-compensating flat balance-spring. Dial, case and movement signed. Diam. 44.5 mm. Thickness: 14 mm.

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Image

Grading System
Grade: AA

Very good

Case: 1

As new

Movement: 1

As new

Dial: 1-01

As new

HANDS Original

Notes

What is a Perpetual Calendar?
A perpetual calendar is a calendar mechanism which, unlike a simple calendar, automatically adjusts to the correct day of the month by accounting for the varying durations of each month, as well as selfcorrecting for the 29th of February during leap years. Audemars Piguet are said to have been the first to produce wristwatches with perpetual calendar and moon phases, in 1924. In 1925, Patek Philippe modified a lady?s pendant watch with perpetual calendar to produce the world?s first instantaneous changing perpetual calendar wristwatch with leap year indication.