1st century BC-1st century AD. A military bronze plumb bob and fitting, one a low conical-shaped and fitted with a massive suspension pin on the back, having holes for the passage of ropes and laces, the other one with biconvex body ending on one side with an open top furnished with holes, on the other side with four protuberances. 146 grams total, 37-47mm (1 1/2 - 2"). Property of a Guildford, UK gentleman; acquired on the UK art market. Such weights were used by the agrimensores of the Roman army to make accurate vertical lines when building or marking the points of camps and cities, used with the instrument called groma. [2, No Reserve]