Evidence of the nature of rotating liquid helium

Earlier experiments by Hall(1) and also by Walmsley and Lane(2) on the angular momentum content of rotating liquid helium II have involved measurements of torque required to set a vessel of liquid into equilibrium rotation. Integrating the resultant torque-time measurements over the angular acceleration (or deceleration) period yielded thereby a measure of the angular momentum acquired by the helium. Since furthermore an integration over the volume of the vessel was involved, such methods produced composite, over all data.