London Pocket Watch Hallmarks

Where does this pocket watch come from and what is it worth?

I have a pocket watch. After digging as much as I could, I found a few things about it but to learn more. face of the watch: http://img41.imageshack.us/i/watchface.jpg/ Innards Pocket Watch: Pocket Watch http://img94.imageshack.us/i/pocketwatchwhole.jpg/ punches (label): Pocket Watch http://img248.imageshack.us/i/pocketwatchhallmarks.jpg/ Innards (label): http://img41.imageshack.us/i/pocketwatch1.jpg/ I need to know more about James Perry & Co. Year: 1775 Manufacturer: Henry James Perry & Co. Serial number?: 5828 City: London Material: Sterling Silver?

Liverpool was once the capital in watchmaking the world, and very beautiful watches come in there. I can not offer something on the machine-specific, there was a lot of watchmakers in Liverpool, and I am not aware of much research has been done on them. I would, however, the question of the date 1775. The watch seems to be a rocket leverage and the anchor escapement was not there in 1775. Other details, including trimming general, and the "Liverpool Windows" (Jewelry in large glass) are consistent with a movement of the period 1820-1840. I can not read the brand very clearly, but 1775 was a "U". 1805 and 1835 have also been a letter U, and in 1835, seems especially more likely to me.