Consisting of two G.clamp with knife-edge top. Comprising a metal bar of 100 cm length having width 25 mm and thickness 4.5 mm. Sharp knife edge with hanger is also provided which moves on metal bar. A spherometer fitted on a cast iron stand (Specially designed for this apparatus) with electric contacts is also provided, but without weight.
It consists of a brass beam 9mm square, one meter long resting on the knife edges of two heavy table clamps. A sharp knife edge with hanger rest on the beam. Two tilting type mirror are also provided for this apparatus but without weight.