[JON-A-TRON] calls his clock a “perpetual clock,” perhaps in a nod to perpetual calendars. But in our opinion, all clocks are perpetual, so we’ll stick with “linear clock.” Whatever you ...

It includes 52 “complications,” including a 400-year perpetual calendar, tide clock, solar and lunar eclipse prediction, a planisphere to show the constellations, and even a thermometer.

It also has a date indicator, with denotations running from 4 to 8 O’clock in a semi-circular line ... The Bovet Récital 21 Perpetual Calendar is equipped with the 13DM05-QPR caliber, which ...