The Breitling Watch Source Forums

Hello, I am new to the forum.
The watch I wanted to get advice on is a very old stopwatch.
The faceplate only carries the letters "Swiss".
On the movement is a a stamped name, that reads "montbrillant watch".
When Leon Breitling founded his company Montbrillant was part of the company name, could this be a watch manufactured around that time?
Any ideas, suggestions for further research, authentication, contacts.
I would estimate the age roughly between 1890s and 1920s. Any thoughts on this?

I appreciate any input
Dietmar