The mechanical mysteries of timekeeping
Mechanical timekeeping is a sort of esoteric secret, and it provides a lot of mysteries to wonder about. Let’s explore one.
Why would a wrist watch seem to lose time or gain time at night but be fine during the day? This is something that has always happened to the most typical watch guy.
Our precious little engines seem to have a life on their own, and a malignant will that makes them accelerate and slow down, their only intent seeming to frustrate our ability to understand their logic.
Well, there IS an answer to this apparently mischievous behavior.
It happens because any mechanical watch performance depends on the position the watch works in.
The longer answer implies knowing a little bit more about watch technique. When you take a look at watch movements, you often find on the bridges a mysterious “adjusted in X positions” etching. (six in the case of the watch on top).
What are these “positions”?
Horologists have discovered the effect of positions on the performance of watches since the 1700, so much that the legendary Abraham Louis Breguet created the tourbillon around 1800, a mechanism that would reduce the effect of positions in the performance of a watch, and improve the overall accuracy.
Finding a way to average these errors had much sense back then, when watches were pocket waches, and were mostly held in two positions: upright, in the pocket, or face up, when left on a table. So, these two became the “standard” positions where the watch was checked and regulated for accuracy.
But the more accuracy, the better, and the overall cost and complexity of the tourbillon (Breguet made just a few dozens of tourbillon-equipped watches in all of his life) was not a universal solution. So, watchmakers started to regulate better-quality watches in other positions as well so to improve their accuracy. The positions became traditionally six:
- face up
- face down
- on the left side
- on the right side
- upright
- bottom up
Why the positions affect a watch performance? They are important because the mechanism is finely balanced, and uses wheels turning on fine pivots inserted into tiny holes practiced between two bridges. As you can readily understand, even a small anomaly in one of these elements would imply a chain effect on the total performance of the watch. Imagine one of them — like the top one — is oiled and the other is not. It would involvesome more attrition on the bottom pivot than the top one. A minuscule effect, but let’s consider that these mechanisms turn all day, and the wheels of an average watch make around 20,000 movements PER HOUR.
Now you can see where a compound effect is going, don’t you?
While regulating a watch in X positions has less importance after the disappearance of pocket watches, as watches are currently worn on a wrist, they still do have some preferred positions, like laying face up (as they normally do when not worn, like when you sleep and lay down your watch for the night).
This is still reflected today in measuring standards like COSC, which defines the nature and performance of so-called “chronometeres”.
When you look at COSC specifications (incidentally, -4/+6 seconds per day), you see that a chronometer’s performance has to be measured in our customary six different positions.
So, coming back to us, when you wear your watch all day, it is highly possible that it has different performances depending on the position you are wearing it. However, in a wristwatch that is used normally, they tend to average each other out in time — except for a single case, when it lays flat on a table or nightstand for the night and stays like this for six/eight hours.
If you experience any other significant variations for unknown reasons, it might mean that there is something wrong with it, and only a careful service from a competent watchmaker would help you solve the mystery.
I explain much more about watches and what goes on inside them in my first book, The Watch Manual. You can download an 8-chapter extract from it for free from the website.