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:
“The dissident does not operate in the realm of genuine power at all. He is not seeking power. He has no desire for office and does not gather votes. He does not attempt to charm the public, he offers nothing and promises nothing. He can offer, if anything, only his own skin—and he offers it solely because he has no other way of affirming the truth he stands for. His actions simply articulate his dignity as a citizen, regardless of the cost.”
—Václav Havel (b. 1936)
“I understood that all the material of a literary work was in my past life, I understood that I had acquired it in the midst of frivolous amusements, in idleness, in tenderness and in pain, stored up by me without my divining its destination or even its survival, as the seed has in reserve all the ingredients which will nourish the plant.”
—Marcel Proust (1871–1922)