The current label for the sundial gives a rather puzzled description of a scene which appears on the top of the lid of the dial: "The design pressed on the lid of the box shows a man sitting and a woman reclining under a tree; the man is writing on the trunk of the tree, and has already written the word 'Angelica' or 'Angelicus'".

Dr Hutchinson was not only able to clear up this ambiguity, but to identify the couple depicted as the characters Angelica and Medoro, from Ludovico Ariosto's sixteenth-century epic poem Orlando Furioso. He points out that both are shown together writing on the tree, and that in the epic they subsequently carve their two names, linked together, over all the trees of the vicinity: "On bark or rock, if yielding were the stone, The knife was straight at work or ready pin. And there, without, in thousand places lone, And in as many places graved, within, Medoro and Angelica were traced, In divers cyphers quaintly interlaced" (Canto 19, stanza 36).

As Dr Hutchinson also notes, this act is crucial to the plot: later Orlando, who loves Angelica, sees the paired names on the trees; his discovery of the love leads to his madness, whence the title of the poem.