Glossary · Complication
Power reserve indicator
A dial indication showing the remaining run of the mainspring before the watch stops.
Explanation
A power reserve indicator shows how much running time remains in the mainspring, via a differential gear that compares the positions of the barrel and the winding works. It appeared on marine chronometers (where an unwound chronometer at sea was a navigational danger) and became a common wristwatch complication in the 20th century.
In the object catalogue
Catalogued objects whose own source record mentions “Power reserve indicator”. The quoted line shows where; it is the seller’s or museum’s wording, not independent verification.
Wristwatch
Greubel Forsey Quadruple Tourbillon in platinum, No. 35
“Source reports describe this Greubel Forsey Quadruple Tourbillon wristwatch, numbered 35 and dating to circa 2009, as cased in a four-part platinum case measuring 43.5 mm in dia…”
Wristwatch
Greubel Forsey Tourbillon 24 Secondes Incliné 18k White Gold Wristwatch
“This Greubel Forsey wristwatch, catalogued as dating to circa 2009 with case number 77, showcases an asymmetric 18k white gold case measuring 43.5 mm in diameter. Designed to ac…”
Wristwatch
Greubel Forsey GMT Sport Earth ‘Blue’ titanium world time tourbillon wristwatch
“This Greubel Forsey GMT Sport Earth wristwatch features an ovoid titanium case measuring 45 mm in diameter fitted to an integrated blue rubber strap. The three-dimensional openw…”
Marine chronometer
Paul Ditisheim Boxed Deck Timepiece No. 98234
“This horological instrument is an individual boxed deck timepiece by Paul Ditisheim, dated circa 1925 by the source. Contained in a single-tier Brazilian rosewood box fitted wit…”
Pocket watch
LeRoy & Cie Oversized Silver Marine Deck Watch
“Power Reserve Indicator: 40 hour wind indicator”
Marine chronometer
Paul Ditisheim Central Second Marine Chronometer
“This Paul Ditisheim central-seconds marine chronometer is numbered 1 011 on both case and movement, and is dated by the auction house to circa 1920–1925. Built under seven Swiss…”