Longcase Clock with 1-1/4 Seconds Pendulum

An exceptional eight-day time-and-strike longcase clock with rare 1-¼ seconds pendulum. The dial is signed, John Clowes, Londini Fecit, at the lower edge of the dial plate, an early placement. Early rising and latched hood. Elegantly proportioned walnut case. The door on the plinth opens to adjust the sixty-one-inch pendulum.

The earliest pendulum clocks used a short pendulum. It soon became apparent that a longer pendulum would be more accurate by reducing error owing to its slower swing and smaller arc. An assumption was made that the longer the pendulum, the more accurate the clock. In an effort to increase accuracy, clockmakers experimented with longer pendulums. The seconds pendulum was about thirty-nine inches long, and the 1-¼ second pendulum was about sixty-one inches long. However, the longer pendulums tended to “take over” the case and make it sway slightly, thereby stopping the clock unless it was firmly affixed to the wall. Air flow of the pendulum itself also affected function. Today, 1-¼ second pendulum clocks are extremely rare, and they exemplify the search for perfection on the part of 17th century scientist-technician clockmakers.