Constant Level Tank

GRAVESANDE – Ring and Ball with Chain. An apparatus for demonstrating thermal expansion, comprising a captive brass ball secured to a mounted brass ring by a chin, Ring mounted on rod with a wooden handle. The ball passes through the ring when cold but will not pass through after being heated

Good quality one piece spinning, rolled rim, polished finish vessel with wooden/bakelite lid fitted with rubber stopper and metal stirrer..
A. Copper 75 x 50 mm
B. Copper 100 x 75 mm
C. Aluminium 75 x 50 mm
D. Aluminium 100 x 75 mm