Steelyard

or Roman Balance, (stel'yahrd.) (Mech.) A balance by which the gravities of different bodies are found, with the a istance of a single weight. It consists of a rod or bar marked with notches designating the number of pounds and ounces, and a weight which is movable along this bar, and is made to balance the body to be weighed by removal to a proper distance from the fulcrum. This forms a lever of the first order. [s. 855]