As so often on cylinder movements up to the early 20th century, this 12 1/2 ligne movement, marked as “FOB 00”, cannot be identified, too. The only reference point is the early FHF hallmark below the barrel bridge:
We have here a common cylinder movement of a good quality, which can be seen for example on the
fact, that all important bearings, except minute wheel and mainspring barrel, contain rubies.
With three gears and the double (bearing and cap jewel) beared balance wheel, there’s a total of 10 jewels (10 Rubis).
The gear train follows the usual construction of these kind of movements: Mainspring barrel, center minute wheel, third wheel, seconds wheel and cylinder wheel.
There’s an odditiy on the mainspring barrel: To achieve an as eveny release of energy as possible, it’s core has got a so called maltese cross, which ensure, that the mainspring has got a certain base tension (limits the running time) on the one, and a maximal tension on the other side.
With this aid, a more or less constant power is possible.
As balance, the usual three leg anular balance is used, which is of course not yet
It beats with 18000 A/h and can be regulated with a long regulator arm.
On the dial side, you see the yoke winding system with external switch at 11 o’clock, which is mostly set by a recessed pin the the case.
On the right, there’s the escapement block, which has got as a unit balance and cylinder wheel. However, on the dial side, the cylinder wheel is already beared under a cock, which is mounted on the base plate.
You can see here the engraved number, 26792, probably an ongoing serial number, but maybe, it denotes a production date, 26.7.1892, which also plausible.