The perpetual calendar is a prime example. A mechanism of breathtaking intelligence, it automatically accounts for the different lengths of months, including the quirk of February in a leap year, and will not need a manual correction until the year 2100. It is a machine that understands our man-made construct of time better than we do.
The minute repeater is another marvel. At the push of a slide, it transforms time into sound. Tiny hammers strike carefully tuned gongs inside the case, chiming the hours, quarters, and minutes in a melody that is both practical and profoundly poetic.