From lines back-to-back: Start a Chase Right, but when the original beaus meet, make a wave where the very centers Trade and Cast Off 3/4 with the wave ends to join the original belles who finish their part of Chase Right and add a Roll at the end. Gives parallel left-hand waves.

Left Chase The Wave - Same as Above except that dancers start a Left Chase and action of original belles and beaus is interchanged. Ends in right-hand waves.