Compass

This apparatus demonstrates that bodies of different density or mass fall through a given distance in the same time in the absence of atmospheric drag

a) Glass tube 600 x 20 mm, fitted with two solid rubber bungs, one carrying 8 mm dia rubber tube with clip for vacuum connection.
b) Same but Glass tube 600 x 50mm dia
c) Same as (a) but with stopcock and can be fitted directly on pump plate