This one had the better of me.
I can't make out the maker - save ending in '& Co' but while ideal to identify and appreciate guidance, is not my primary query.
There is no Assay office but the date letter (x) has maybe a crown above it and while it most closely matches Sheffield 1797 the crown (if it is a crown) above the letter 'x' does not. Everything else is in line,lion passant, duty mark of Geo. III, correct oval cartouche for the assay/date.
Seeking confirmation that this is Sheffield 1797 and if not - confirmation of an alternative.



Cheers from 'downunder'.
Stuart.