Rare Royal Worcester Trembleuse Cup and Saucer Ca. Makers Mark Stamped "P" on cup for 1879. Makers Mark Stamped "M" on saucer for 1877. Has wear but no chips or cracks (please see all photos). Trembleuse cups and saucers were designed to prevent spilling for a person who suffered from trembles (trembling hands).
The saucers deep inset holds cup firmly in place. Last Photo is Example from Cooper Hewitt, Smithsonian Design Museum (with permission). Please make sure to use enlarge photo option or zoom to review clearer pictures of the item. Let us know if you need additional pictures.