Puckerings has dated this piece to the 1800s.
It in under each of these handles (removed by unscrewing the bolt) that the makers mark is present (crossed keys into a shield) for the Sheffield silversmith, Henry Wilkinson & Co. and dating to the very early Victorian era, around 1840, making this pair nearly 170 years old.

The traditional way of incorporating a family or armorial crest into an Old Sheffield Plate piece is by sinking a solid sterling silver ingot into the area to be engraved, this way no base metal (copper) would show through the engraving. You can see a rectangular shadow to each dome where this was undertaken. Each has their original engraved Crest with the motto "Manus Justa Nardus".

Wonderful condition, a few minor spots of copper showing as it should do, mentioned purely for accuracy. You won't top these! The larger dome measures 18" x 13 1/2" and stands 11" tall; the smaller dome measures 14" x 10 1/4" x 8" tall to top of handle.
Item ID: 35250
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Puckerings has dated this piece to the 1800s.
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