The stream lines are as represented in the annexed diagram, in which the region of translational velocity greater than wave-propagational velocity is separated from the region of translational velocity less than wave-propagational velocity by a cat's-eye border pattern of elliptic-whirls.

Report of the Fiftieth Meeting of the British Association for the, Advancement of Science, On. a Disturbing Infinity in Lord Rayleigh's Solution 'for Waves in a, Plane Vortex Stratum (p. 493)