Here is what I have...

various

The one on the left was my grandfather's smallish Seth Thomas. He died in 1930. It still runs, but not very long and probably needs tinkering. The one at top is an Elgin...unknown date & origin, and does not run. Below it is an empty case which unscrews....and on the right is something I never understood. It is just a glass 'form' in the shape of a watch. Anyone know what this is called?

Here is a closer view of the Seth Thomas (in original box). It has the nice design on the case, and his initials in the inside back.

Any general opinions?