Richard Devonshire was apprenticed to George Burrows, a well known maker of sugar tongs.  He registered a mark as a spoon-maker on 14^th October 1819.  His mark is rare.  These tongs are standard fiddle & shell pattern but notice that the die has been stamped a little off-centre.  Given that he did not make very many sugar tongs, perhaps he was not terribly good at it!