Leave it to the Swiss to have pioneered what are called complications, or features beyond the display of time. Take the perpetual calendar, calibrated precisely until the end of the century. It can tell you the day of the week, the date, and the month – accounting for leap years, says Jaeger-LeCoultre's Matthieu Sauret. “It knows everything,” says Sauret. “There is no electronics at all in this timepiece. Everything is gears, gear trains, wheels, and springs.” #mechanicalwatch #watch #swisswatch