WW1 Trench Watch

[Knightslad]

 I’ve attached a few photos of a watch I recently purchased, which I know has an ebauche made by Fountainemelon because I found their stamp. I’ve looked at photos of every Fountainemelon movement I can find, but none of them match. There is an inscription on the back indicating that it was a gift in memory of the “Guerre 1916/17" and the earliest repair mark I can find is from 1917, so I’m assuming it's from about that date. The unusual thing about this trench watch is that it has a date hand function, which seems to have been fairly rare, at least this early.  I have found that a Swiss watchmaker named Alfred Hammerly patented a date hand mechanism in 1915, but so far can find nothing about him, his patent, or early examples employing his ideas. I’ve attached a couple of photos, one of the date mechanism and one of the watch face.

   It also seems slightly unusual in that it has 13 jewels, since the 3rd and 4th wheels only have jewels on the mechanism side, but not the dial side. I assume this is because the jewel settings would sit too high on the plate and interfere with wheel that advances the date. I’ve also read that some of the early date-hand watches had to have the date set every day, but this one advances the date. It also has a pusher at about 11:30 that stops the date hand from advancing while setting the time.

   It appears that Oris was one of the first makers to supply a wristwatch with a date hand, but not until the 1930’s. Since the date hand is sometimes mentioned as the first wrist watch complication I’m thinking that this watch might be somewhat rare, and I would be immensely grateful if you can shed any light on what it might be, or if you have any conjectures.

[CYCLOPS]

that is a rare bird indeed, the minute hand is cool too, a lot of members are going to want to see a picture of the movement, .....Merry Christmas

[Knightslad]

[RichardHarris123]

Is that an English lever? 

[nevenbekriev]

The picture is taken in moment of moving of the escape wheel, that's why it looks strange. But it is regular swiss lever.