This is what a single stone skip looks like at 1000 frames per second. As the stone hits the water, it creates a cavity which provides a ‘ramp’ for the stone to climb before leaving the water as a projectile, only to repeat the process until its speed is too low to do so. By spinning the stone, its orientation becomes more robust to the inevitable torques imparted to it with each impact. The full video is fascinating and includes a different technique that works with rocks that look impossible t