Epact Scientific Instruments of Medieval and Renaissance Europe

The second face of the instrument carries at the centre the hour diagram for an Italian hours dial (9 to 23) for latitudes 43 and 44? with meridian line named to the right and a calendar scale marked to the left. Beneath the diagram is a scale of 90? reading to one degree and beneath this the inscription 'QUADRANS AD LATITVDINEM GRAD{UUM} XXXXIII et XXXXIIII'. To the left of the calendar scale is the signature to the right of the meridian line the information 'LINEAE PVNCTORVM POST MERID{IEM}' ('Dotted lines afternoon'). Above the hour diagram is a shadow square of twelve divided in four numbered groups of three. At the top of the instrument two pierced sights are set with, between them, the dedication 'AD. MARCELLVM. M.'. The handle carries a scale of three rings the middle one of which is a scale of months, the outer the initial letters of the zodiac signs (two to each month), and the inner a series of twelve numbers '7 8 6 6 5 5 4 4 4 3 4 5' represented by the letters of the alphabet 'A' to 'H' (1 to 8). At the centre of the diagram is the number 'XIII'.

Provenance: one of a group of twelve instruments which belonged to Professor Pietri Marchi and were presented to the museum by the heirs of his daughter.