Trying to date a silver pocket watch

When my father died my mother gave me a tin containing three pocket watches which belonged to my Grandfather. I’m trying to work out how old they all are but struggling to identify the hallmark on one of them:

The watch movement is a key wound fusee chain which I believe was popular in the mid 1800’s. The closest I can find online is 1829 but I’m not sure this is right particularly as there is no monarch stamp.
Many thanks for any help, Steve.

1829 is exactly right; well, to be strictly accurate 1829/30 as the assay year for London started on 29th May. The maker of the case was John Harris, a specialist watchcase maker. The monarch’s head mark to which you refer is a duty mark which shows that the relevant tax had been paid on the item. However watch cases, both in gold and silver, were exempted from taxation from 1798 so there is no duty mark on them after that date.

Phil

Thank you so much Phil, that is really very helpful. Much obliged.