"He tries to explain the puzzle of how a trout can make a standing jump several meters high against the enormous force of a waterfall. His conclusion: the spiraling free-falling water... creates a wake at the center. The trout searches out this counter-current... the mass of the falling water opens... a gap for a fraction of a second, it slips through and, sucked up the center by the countercurrent... is thrown up... This makes it easy to visualize the inner energy... in... clouds... wind and the water. Birds behave... much like trout..."