Part IV. An experimental study of the collapse of liquid columns on a rigid horizontal plane

An experimental study has been made of some aspects of the phenomena accompanying the collapse of liquid columns on to a rigid horizontal plane with air as the outer medium. The cases covered include the two-dimensional collapse of rectangular and semicircular sections, and the three-dimensional axial collapse of right circular cylinders. As the columns collapsed, the fluid spread across the horizontal plane, attaining a maximum velocity, which, in the two-dimensional cases, was proportional to the square root of the original height. It was not clear whether this proportionality would hold for the axial collapse of cylinders. If it did, then the factor of proportionality would be some 25 % lower. In the two-dimensional cases the top of the residual column accelerated downwards to a maximum velocity proportional to the square root of the product of the original height and the original height to base ratio. The nature of the subsequent retardation indicated that the downward velocity probably approached zero asymptotically with time.