Linear Expansion Apparatus, Micrometer Type, Economical

Two cast metal legs joined together by a pair of plated metal rods, with each leg having provision for horizontally supporting the ends of plated brass tube about 50cm long. The tube has a riffled nozzle near each end, facing opposite each other for use as inlet and outlet of steam, and another outlet at the center with holed rubber bung for inserting thermometer to measure the inside temperature. The test rod is inserted in the brass tube supported in rubber bungs at its each end. At one end is fitted a micrometer screw head reading to 0.01mm. A 4mm termils provided on each leg for connecting an electric bell or galvanometer to indicate make/break of contacts. Supplied complete with 3 metal test rods, one each of copper, brass and steel.