Bronze; 29.5 cm (open), 14.5 cm (folded)
Naples, MAN; inv. 84/146
Pompeii, or Vesuvian region
First century AD

This instrument, made of two small rectangular bars hinged together, constitutes the Roman unit of linear measure: the length corresponds to 29.5 cm, the Roman foot. The subdivisions of the foot are indicated by the incised marks on the faces of the bars.