It is even used as a measure of the season of the year, with painfully short days in winter, longer in summer. And yet, it is the moon, the sun's strange, celestial little cousin, that appears on the clocks. A fact worth investigating. So let's delve into the history of the lunar phase complication and its significance for horology.
The moon has been used as a calendar indicator for 35,000 years.
No, the point is not in the wrong place, we're talking about THIRTY-FIVE millennia here. He's referring to cave paintings. It's something that every civilization on Earth has used in one way or another. And there are good reasons for that.
Unlike the sun, which shifts ever so slightly from day to day, the moon changes much more dramatically. There is a visible difference from one night to the next as it moves through its monthly cycle. This fact makes it much clearer and easier to use as a timekeeper.
In horology terminology we would say that it occurs at a much higher frequency than the sun. These clear changes are the reason for the Chinese lunar calendar among very many others.
Then there is its effect on the real world. Tidal changes have historically been vital for anyone living in coastal waters. Given trade, fishing and countless other uses. Therefore, understanding the moon and how its various phases affect tides is a practical necessity.
Of course, understanding why and how the moon does what it does has come a long way. Especially since landing on it, but it has always been one of the most important aspects of human civilization.
But nowadays, unless you're a fisherman, it's also one of the most unnecessary complications you can put on a watch.
Now this is not necessarily a bad thing. Since the 1970s with quartz and more recently with cell phones, the wristwatch has been an obsolete timepiece. But we still love it. And that's without mentioning the adornment of metiers d'art. A realistic engraving of Cambodian ruins does not guarantee COSC certification.
And yet, nowadays it is one of the most common complications that we encounter in a particular class of watchmakers.
Especially when it comes to clothing watches, and we'll touch on that. But before Patek Philippe put the first phase of the moon on a wristwatch. Because of course it was Patek Philippe, this complication already had a rich mechanical history.
One of the oldest known, powerful examples of mechanical phasing of the moon is the Antikythera mechanism.
Who recently became famous as Indiana Jones' latest McGuffin. While it's not some sort of time mapping machine, it's a piece of pure innovation that we've discussed in the past. We interviewed Ludwig Oeschlinn, the creator of the Ulysse Nardin Freak and the man who figured out what the rotating, surviving mechanism was.
It is a mechanical calendar and shows, among other things, the irregular movement of the moon around the Earth.
It took only a few millennia for Europeans to get the idea. During the Renaissance, astronomical clocks were often found in churches and city landmarks. These clocks were a historical oddity for an event.
They represented the sun and the moon moving around the Earth. They got the part of the equation that involved the moon. But it was found to be a bit dubious when we started looking more closely at the solar system.
The phases of the moon reappeared in their final form in Germany in the 1700s.
It became standard to use the semi-circular space above the otherwise rectangular dials to depict one half of a disc with two moons. This meant that the hand moved from the new moon to the full moon and back again. Before being repositioned as the disc rotated.
It was inspiring, really useful (at the time) and perhaps most importantly, it was absolutely beautiful.
In the following centuries, horologists tried to outdo each other to create more elaborate phases of the moon. They were often the most important point of the dial. With happy moons, melancholy moons, silver, gold or painted moons, exaggerated or redrawn moons. In all shapes, sizes and backgrounds.
Some brought other astronomical compositions. But the moon phase itself soon became one of the most popular additions to fine watches.
This kind of decoration, however, contrasts little with how wristwatches evolved. That is, in the trenches of the First World War. Watches as we understand them today - not tiny, Breguet-style jewelry - were utilitarian and robust.
This is largely why it took until 1925 for Patek Philippe to introduce it to its collection with the 97975 diameter.
It is the movement inside the first wristwatch with perpetual calendar. And it is largely the reason why the two cases are linked in the minds of many collectors.
Perhaps the biggest impact came from the Rolex 8171 from 1949. Another calendar watch, the 8171 placed the moon phase on its own at six o'clock, making it the centerpiece of the dial. Since then, it has rarely been the moon phase that mixes the composition. Even its mode of operation has rarely changed since then.
Despite its high issues, the moon phase is actually one of the easiest cases to implement a complicated operation, provided your watch already has a date.
All you need to do is connect the moon wheel to the date, which will rotate it a little once every day. Because it takes a whole month to make a rotation, it's not a tinkle that you'll notice. It's an elegant solution and quite accurate. This is the kind of moon phase that 99 percent of watches will use. But it's not the only one.
Recently, Christopher Ward presented what he calls the perpetual motion phase of the moon, aptly named C1 Moon Phase. They achieve this by linking the moon phase separately to the date with a unit, so that it moves continuously, slowly. It also separates the date and moon phase, something you need for a really accurate capture of the complication.
There are also versions that use awesome display methods, such as the Hermes Arceau l'Heure de la Lune, which goes completely off the rails and moves the «dials» along the moon hands instead of the other way around.
It's one of my favorite publications out there. Or there's the Ochs & Jnr Selene Nebra Moonphase, which actually pays homage to this early Greek astronomical watch - fitting as it was designed by none other than Oeschlinn.
However, if there is one watchmaker active today who is recognised as the master of the moon phase, it is Andreas Strehler. His Sauterelle à Lune Perpétuelle holds the Guinness World Record for the most accurate moon phase.
In numbers, that's because it will be off by one day every 2.045 million years (although since being awarded the world record in 2014, the industry has continued to improve the accuracy - see the IWC Eternal Calendar).
It will take longer than the entire history of moon phase clocks - of man using the moon as a calendar in general - before it will need to be adjusted.
How? With an incredibly complex set of calculations and patented subtle manipulations that are difficult for experienced watchmakers to understand. Let alone a humble watch writer. Why? Because, although the phases of the moon are not strictly useful, they are linked to multiple aspects of why we love watches.
They are beautiful, inspiring, wonderfully redundant; they tap into a millennial fascination with both the night sky and the passage of time.
They are one of the oldest interventions in watchmaking and, whether it's a simple addition to the date wheel or an impressive tour de force of mathematical obsession, they are here to stay for many more millennia.
By SAM KESSLER
Source: oracleoftime.com
