This is a hell of a F.P. Journe watch from about 2004-2005 and really resonates with me because it epitomizes what I like in the brand. Some of their other watches just feel like too little for too much, but this Tourbillon Souverain came out when the brand was smoking hot, and everyone was paying attention. An earlier F.P. Journe's Tourbillon Souverain was released before this model, but this watch added a lot to the timepiece and refined the looks of the face. Aside from looking cool, this timepiece has a ton of interesting things going on inside.
For one thing, you have a very clean exhibition of the tourbillon on the dial instead of looking through to your wrist between sandwiches of sapphire crystal, you see the tourbillon escapement on a plate of gold with perlage polishing. Classy and sensible. Then you have the watch dial that is smaller and off centered and a subsidiary "dead seconds" (I will get to that in a bit). Don't miss the power reserve indicator as well. The full name of the watch is the ridiculous sounding "F.P. Journe Tourbillon Souverain - Remontoir d’Egalité avec Seconde Morte," but I will spare you that title by not continually repeating it.
The watch case itself is in platinum and 40mm wide. There are all the iconic F.P. Journe design elements to the Tourbillon Souverain that I expect from the brand. This includes the style of the dials and the hands, not to mention the colors, and of course the flat little crown that actually works quite nicely. The two symmetrical windows on the dial work well off of each other. Even though there is so much going on in the watch. At 40mm wide, it is relatively medium sized by today's standards, making the entire piece classic looking, and harder to make in the smaller size.
Aside from what you see on the dial and through the caseback window, the watch has two other very important complications. One is sort of a novelty for fun, and the other is an important part of the watch's ability to keep accurate and reliable time. The latter is a constant force escapement which is also known as a remontoir. This complication is used to control the force that is moving from the mainspring to the escapement and then to the watch. It makes sure that the force moving through this train is constant, regardless of how tightly wound the mainspring is. What happens with a mainspring, is that the force it releases when it is tightly wound, is more than the force it releases when it is almost unwound. This effect the rate results of a watch making it less accurate. A constant force escapement helps remedy this issue, which makes having a remontoir nice in luxury mechanical watches. You don't necessarily need a remontoir to have more accurate mechanical watch, but it is one good means of going so.
The other complication the watch has is what is know as "seconde morte" or "dead seconds" in English. Basically creates a seconds indicator that moves in steps from one second to another just like a quartz watch has a ticking seconds hand. We know most mechanical watches to have sweeping seconds hands, but this is the one exception. It is actually true that having a dead seconds dial makes certain types of timing more accurate - but really here it is just a novelty that F.P. Journe enjoyed throwing in. You can see more of it working in the video.