Renée Tschumi
Bench one · 41 years
Owns the escapement. Poises every balance by hand, sets the beat, and runs the six-day timing in six positions that decides whether a movement is cased or goes back on the bench.
The story
It started as a repair shop.
Fifty years of other people’s movements, then one of our own. That order matters, and it is the reason the Calibre 312 is shaped the way it is.
Aeterna was registered in Geneva on 4 March 1948 by two watchmakers who had spent the previous decade servicing other houses’ chronographs. They took the first floor of Rue de Carouge 14, set four benches along the window wall, and kept the servicing trade running for eleven more years before they sold a watch with their own name on the dial.
The address has not changed since. Neither has the floor. In 1963 the building’s owner offered us the floor above and we said no. The offer has come back three times and the answer has not moved. A second room means a second standard, and then somebody has to decide which of the two is the real one. Four benches is what fits along that window. Four benches is what we have.
For the first fifty years most of the money came from other people’s movements. That is not a modest origin story, it is the reason the Calibre 312 looks the way it does. Fifty years of service work teaches you which parts fail, which parts cannot be reached with the movement still in its case, and which clever idea is going to cost an owner four hundred francs in 2041.
The drawing, 1998
The Calibre 312 was drawn in 1998 by the four people who still build it. The first sheet carried 344 parts. It ran, and it was heavier and harder to service than several of the movements we were being paid to repair.
Eleven revisions followed over fourteen years, and every one of them took something out. Revision three removed the sliding gear and put the chronograph on a column wheel, which cost more to make and removed two ways for the watch to fail. Revision six removed the second barrel: one mainspring now, wound by hand, still holding seventy-two hours. Revision nine replaced two bridges with one, which is why the dial side reads as a single drawing instead of a stack of plates. Revision eleven, in 2012, removed a screw.
That left 312 parts and 37 jewels. Nothing has been added to the calibre since, and nothing is going to be.
The number, 2016
By 2016 we had a finished movement and no decision about how many to make. The argument took most of that year. An open-ended line meant hiring, hiring meant a fifth bench, and a fifth bench meant the floor above.
So we used the part count as the edition. Three hundred and twelve parts, three hundred and twelve pieces, across twelve references: nine in titanium at twenty-six each, two in rose gold at thirty-four each, and ten in king gold. When the three hundred and twelfth watch is cased, the tooling comes off the line and the Chronographe 312 is finished.
A limit costs money. We have turned away orders we could have filled and we will turn away more. We cannot tell you what one of these watches will be worth in twenty years, and anyone who tells you is guessing. What we can tell you is the number, that it will not move, and that you can check it yourself: the register is published, and it has 312 rows.
Today four people build the watches and two more answer the telephone, pack the boxes and keep the register. That is the whole company. If you write to us, one of six people reads it. If you visit, one of the four will put a loupe in your hand and show you the part they are worried about that week.
