I recently purchased a Seth Thomas carriage clock on eBay. It has the D105 movement in it. I have not completely torn down the movement, but I am trying to understand what the mechanism in back of the dial and in front plate of the movement is for.

The fan in the rear governs the strike. I am trying to understand what the fan in the front does.

Another view.

Ken, I don't have a clue, but I did find reference to another D105 on that "other site". And found that some of the components are gold plated.

Here is a photo of the clock. It is listed in Tran's Seth Thomas book third edition as Carriage No. 7. There is no evidence that anything is missing from the clock, so whatever the function of the extra train, it is integral to this movement.

Rear view. Height including handle is 9 inches.

I've been studying this and coming up short. Can't find anything close to it. Nice clock though!

What is that pin sticking out toward the edge of the movement, just below the fly, and also the arbor down below with the arm extending into the movement?

That pin is an arm that extends down the front and activates the train to move.
The arbor has a post on it similar to the post that counts the hour on a striking clock. It is hard to see just what it does, and I have not fully disassembled the movement.

Very nice clock.
Not an expert, but would the face cutout be for day,date or month?
Happy gear meshing.
Mike

COULD THE FAN IN FRONT CONTROL SOME TYPE OF A REWINDER ,REMONTOIRE OR WHAT EVER. THE CUTOUT IN FRONT IS THERE TO EXPOSE THE ESCAPE WHEEL. DOES THE CLOCK RUN?

I keep thinking alarm clock, but don't really think it is.

The clock does run. I think the tension on the minute hand is a bit weak, and it does need a complete service.

Ken, Found an old post here on a 103A movement I worked on, that shows a picture during the teardown.
Not exactly the same movement, but internal pictures might help.
https://ihc185.infopop.cc/eve/f...6029761/m/9713967087

Dave, I have serviced the 103 A movement. This movement is much superior. I will be tearing it down soon, so I will probably provide some pictures and hopefully an explanation for the function of the additional train.

I believe that the additional train is used to wind a small mainspring behind the removeable platform that holds the balance wheel with its gear train.