When it comes to dive watches, you have no end of choice, it seems, even within the higher-end mechanical realm. However, when it comes to being truly functional as a dive watch, you generally don’t get much more than an elapsed time (via the bezel). Oris is changing that with their new Aquis Depth Gauge.
At first glance, this watch looks just about like any other watch you might pick up. A closer look at the crystal will show where this one is differentiating itself, though. Look right up at the 12 o’clock mark – you’re going to see an opening there; this is definitely a departure from the smooth (and solid) surfaces we’re used to seeing on our watch faces.
This is actually an opening into a channel that runs counter-clockwise around the crystal. Water flows into this channel (don’t worry, there’s a gasket sealing the channel off from the bezel and the case), indicating (in a deceptively simple manner) how many meters down you are. How exactly does this work? All due to the principle that Henry Boyle published in 1662.
His law states (and I’m simplifying things here a bit) that pressure and volume are inversely proportional. In other words, as one measure doubles, the other halves. If you want to read some more on this law, you really should check out this Wikipedia article.
So how does this work for the watch? In that channel carved into the crystal, you have a fixed amount of pressurized oxygen. As you dive down, water pressure forces its way into this channel, and compresses the air at a known rate. This ingeniously leads to the printed inner bezel letting you know (where the light and dark segments intersect) exactly how deep you are. This is particularly clever due to the fact that you’re getting an instantaneous readout – no delay (however slight) there might be for a mechanical or digital gauge to translate the pressure into a human-readable number.
That’s not all there is to this diver. You also have a unidirectional divers bezel around the extra-thick crystal, complete with a ceramic inlay. This overall is a fairly big watch at 46mm in diameter, plus the necessary thickness to house the depth channel in the crystal, the ETA-based Oris 733 automatic movement, plus net a 500m water resistance rating.
Coming in at just under $3,600, this is definitely a watch that deserves more than a life of desk dives, whether it’s on the rubber strap or stainless bracelet. If you’re finding yourself in the Venn-diagram intersection of recreational diver and watch afficianado, this is definitely one you’ll want to check out. I’m not a diver myself, but I can really get behind the tech in this watch.