Isochronism

On why your team keeps perfect time for three weeks and then invents a new calendarThere is a word for the thing every executive claims to want and almost none of them are willing to engineer. The word is isochronism, from the Greek for equal time, and it describes the single most demanding property a mechanical timekeeper can have - that its oscillator beats at the same rate regardless of how much force is pushing it. A watch does not receive a steady supply of energy. It receives a mainspring, which is a coiled strip of steel that is furious when fully wound and apathetic by Thursday. Torque at hour one and torque at hour fifty are not remotely the same quantity. And yet a good movement keeps the same rate throughout, which means the timekeeping is somehow indifferent to the very force that drives it. Understand that this indifference is not a gift of physics. It is a fight against physics, won incrementally over three centuries by people with very small screwdrivers and no patience…