Power Reserve Indicator
Some high grade watches have an extra dial on the face indicating how much power is left in the mainspring, often graduated in hours the watch has left to run. Since both the arbor and the barrel turn, this mechanism requires a differential gear that measures how far the arbor has been turned, compared to the barrel.
Read more about this topic: Mainspring
Famous quotes containing the words power and/or reserve:
“There are times when they seem so small! And then again, although they never seem large, there is a vastness behind them, a past of indefinite complexity and marvel, an amazing power of absorbing and assimilating, which forces one to suspect some power in the race so different from our own that one cannot understand that power. And ... whatever doubts or vexations one has in Japan, it is only necessary to ask oneself: “Well, who are the best people to live with?””
—Lafcadio Hearn (1850–1904)
“Mutual repect implies discretion and reserve even in love itself; it means preserving as much liberty as possible to those whose life we share. We must distrust our instinct of intervention, for the desire to make one’s own will prevail is often disguised under the mask of solicitude.”
—Henri-Frédéric Amiel (1821–1881)