The Power Reserve Complication
Watch & Bullion15 November 2017 | 2 min read
There are a lot of complications in the watch world. With the advent of technology, however, a lot of them have lost their unique value, being able to be reproduced easily by apps.
One complication however that to this day remains incredibly useful is the power reserve indicator or reserve de marche as originally known in french. As a concept it is basically the fuel gauge of the mechanical watch. This complication found use particularly in the world of seafaring, where nautical clocks where used for determining the location of a ship. This would work by using the reference time and comparing it to when the sun would set. If the clock would run out of energy though, this would render it useless, and therefore the power reserve indicators where used to prevent this disaster.
A Nautical Clock with a Power Reserve Indicator
As wristwatches became more common watch brands came to conclude that this feature would also be highly useful in mechanical wristwatches which are manually wound. This lead at the end of the 1940s to the first serial produced wristwatch with a power reserve indicator to be introduced, the Jaeger-LeCoultre Powermatic Calibre 481 automatic.
Really how important this complication can be was sadly demonstrated in 1891 by what is now referred to as the Great Kipton Train wreck. 60 kilometres from Cleveland Ohio, 6 men lost their lives. The cause: a slow running watch.
A Jaeger Le-Coultre Powermatic with Power Reserve indicator
Nowadays the power reserve has remained one of the most practical complications around, and that is because rather than adding a feature, it complements the watch as a whole. Not surprisingly then that it can be found on some of the most appealing watches in the world. To end on a good note, below some of the Classics which utilise the power reserve.
F. P. Journe Octa Power Reserve
A. Lange und Söhne 31
Grand Seiko Spring Drive 8 Day Power Reserve, which displays the power reserve on the backplate