31 July 1998
Vol 281, Issue 5377

About The Cover

COVER The structure of three-dimensional chaotic flow of a viscous liquid in a mixing tank is revealed by the intersections of fluorescent dye lines with a laser sheet. The dark islands (regions of poor mixing) are cuts of tori that may wind around the tank several times. Chaotic regions with good mixing appear as highly stretched and folded dye streaks surrounding the islands. See page 683. [Image: G. Fountain, D. Khakhar, J. M. Ottino]