Grandmother's China Cabinet Clock

by Julie
(Grapevine, Texas, USA)

This clock sat in my Grandmother's China Cabinet when I was a child. It is now in my posession.

It is black and gold with a standing cylindrical shape, about 3 inches in diameter and about 6 inches tall. It has mechanical flip numbers (I loved to watch it flip when I was younger).

Markings on the bottom identify it as J. Mergenhagen, West Germany, 8 days, 7 jewels. There is some type of a key taped to the bottom.

It works, but is not keeping accurate time. I would love to know if there is a way to adjust the timing, but I don't want to mess with it without knowing how to work it properly.

Any information about the workings or history of this clock would be greatly appreciated! Not sure if relatives brought it over from Europe or if Uncle may have brought it as a gift while working in Londing during 1960's?