Manually operated mercury vacuum pump, 2000

Museum of the History of Sciences, Ghent University, Ghent, Belgium. Caption reads: "Kwikpump volgens [according to] D.H. Geissler, c. 1900 Franz Moeller, Dr. G's Nachfolger Bonn a/Rh." Crank raises and lowers the outside reservoir. Proper opening and closing of the valves produces a vacuum within the apparatus, which becomes more rarefied with each cycle. In 1857 Heinrich Geissler invented the tubes that bear his name. Each contained a nearvacuum and was used to demonstrate and investigate the effect of electricity on the material left in the tube.