  The JHU turbulence database [1] can be used with a state of the art
visualisation tool [2] to generate high quality fluid dynamics videos. In this
work we investigate the classical idea that smaller structures in turbulent
flows, while engaged in their own internal dynamics, are advected by the larger
structures. They are not advected undistorted, however. We see instead that the
small scale structures are sheared and twisted by the larger scales. This
illuminates the basic mechanisms of the turbulent cascade.
