Nature 196, 1080 - 1081 (15 December 1962); doi:10.1038/1961080b0

Bath-Tub Vortex

ASCHER H. SHAPIRO

Massachusetts Institute of Technology, Cambridge, Mass.

PERENNIALLY one hears controversy regarding the direction of the vortex in the drain of the bath-tub or the kitchen sink. Some claim that the direction of swirl is always the same in the northern hemisphere, and that in the southern hemisphere it is always opposite to that for the northern hemisphere. Others claim that there is no unique direction of swirl in either hemisphere.