This is a "first attempt" at posting. If successful, I will provide additional photos as separate messages.

NOT sure whether the inscription is supposed to be "Wm. Step Henson" or "Wm. Stephenson"

Additional photo

Additional photo-hallmarks

ouch!
Nice one accept for broken chain.

In "Watchmakers & Clockmakers of the World" by Loomes, William Stephenson, London is listed as active 1794-1820. I will see if I can find any other info.

A close up of the case hallmarks could help date it.

For some reason, I hadn't considered "London" as part of the maker's name but rather the location of manufacture (!!!!). I'll work on getting a better picture of the hallmarks. THANKS for the info!

I'm adding two closeup images of the hallmarks

And the other...

Sorry if I confused you, Stephenson was working in London, I forgot a comma after his name.

The case marks are the lion with the paw raised is for .925 silver, the lion's head with the crown is London, the lower case "u" is the date & if I am reading the chart correctly the date is 1795. The bust of a person is the duty mark showing tax on the item had been paid to the crown. Last the letters "IA" are the makers mark, so far I haven't found who that was.

Tom: Many thanks for your research. This is a "new" area for me. A relative gave me several old pocket watches years ago. More recently, I was talking with a friend who is very knowledgable about watches about them, and I sent him some pictures of them. He knew all about the others (there is another one that I'll post later) but this one had us "stumped."