====== Magdeburg Hemispheres ====== {{:physicsdemos:thermodynamics_and_fluid_dynamics:thermodynamics:magdeburg_hemispheres.jpeg?400|}} When vacuum is applied to the volume enclosed by a pair of hemispheres they cannot be pulled apart. A valve on one of the hemispheres may be used so that the pump can be disconnected without disturbing the vacuum inside the apparatus. P1 PIRA DCS 2B30.30