The clock mechanism with the falling weight on the right and the 4m pendulum. Image Credit: Arthur Harvey

Perth Observatory is home to some of Western Australia’s most historical clocks. Perhaps most famously the heliochronometer was designed by the first Government Astronomer of WA, W E Cooke. We have two Victor Kulberg astronomical regulators and two Synchronome clocks, designed by W H Shortt, one of which we hope to have to operate soon.

Now in Nannup, master clockmaker Kevin Bird has realised over a decade’s work by commissioning the world’s largest wooden pendulum clock. This clock combines the beauty of local timbers – the sheoak selected for its stability – with a traditional design incorporating falling weights driving a gear train with a deadbeat escapement. The time is displayed on a 2m dial on the building’s façade.

Christiaan Huygens, inspired by Galileo, invented the pendulum clock in 1656. Of course, astronomers know Huygens well; among his discoveries is Saturn’s moon Titan. The space probe which landed on Titan in 2005 is named after him. At over 6m tall with a 4m pendulum, this is a very impressive clock by any standard.

The escapement showing the gears laminated for stability. Image Credit: Arthur Harvey

With such large gears, it might seem too big to be able to keep time accurately. Not so; this clock, with its involute shaped gears, is accurate to 1 minute per week! The clock incorporates particular features such as the clever re-wind mechanism and the means of transmitting the impulse from the escapement to the pendulum; these elegant solutions attest to the designer’s deep understanding of the clockmakers’ art as well as his woodworking skill.

I have had the good fortune to see the Astronomical Clock in Cremona, the Gros Horloge in Rouen, the Beauvais cathedral clock with its 59 dials and Cooke’s heliochronometer (a name a few) but none were more special than the Nannup clock with the added bonus of being able to talk with the master clockmaker, Kevin Bird himself.

Unfortunately, if you haven’t already visited this clock, the opportunity to do so may be lost as I understand it has been removed from its location in Nannup. Perhaps it will be re-installed elsewhere; certainly, this modern wonder deserves to be on display.

Close-up of the gear train for the Nannup Clock. Image Credit: Arthur Harvey