Some years ago while traveling in Italy, I saw a clock in a shop in Florence. I thought the design really fascinating. The clock was designed by Dutch artist Wil Van Den Bos.

A couple of years later I went searching for the clock and found it on Ebay, of course. Made in China, it uses cheap electric clock motors and is made of plastic painted silver, but it works and it’s cool. While there are many different models, the two (above and below) appeal to me the most. The one shown below (called imaginatively the “Big Gear Wall Clock”) is novel because the dial moves against a stationary hand.

According to Wikipedia, this design–a fixed hand and moving dial–was common up until and including the 14th century. On a visit to the British Museum in London last year I saw the Cassiobury Tower (Turret) Clock, which is huge, and dates from around 1610. Its design is similar to the earliest tower clocks dating back to the 1300s. The first tower clocks didn’t have faces, but tolled on the hour, usually counting the hour with the same number of bell rings. Since many townsfolk were probably not within sight of the clock, it made sense just to indicate the time by a toll of the hour. As clock mechanisms got more accurate it was possible to add a minute, and even second, hand. I can’t find anything on the internet to tell me why clocks went to moving hands on a fixed dial, but I have a theory (just like Anne Elk.)

My theory is (and this is the theory that is mine), is that moving a dial takes a lot of energy. Dials are big and heavy. (The dial on the Cassiobury clock is about 12 inches in diameter–it clearly was not meant to be seen by townsfolk!) Hands are relatively lightweight, and consequently it’s far easier to move hands against a fixed dial than a dial against fixed hands. It also explains why the Big Gear Wall Clock is made of plastic rather than metal. It would be nearly impossible without much larger motors (and an energy source larger than two D cell batteries) to move a metal dial of about 20 inches in diameter around, even with gears and low friction. That’s my theory…

I have recently found that there are a few websites dedicated to making clocks out of wood, and some of those designs include a moving dial and fixed hand. Maybe I’ll find the time to make one…