The American psychologist George Stratton conducted two experiments using a lens system that effected an 180º rotation of the retinal image in his right eye (his left eye was kept covered). The first experiment involved wearing the device for 21.5 hours over the course of three days (1896); the second experiment involved wearing the device for 81.5 hours over the course of 8 days (1897a,b). In both cases, Stratton kept a detailed diary of how his visual, imaginative, and proprioceptive experiences underwent modification as a consequence of inverted vision. In 1899, he performed a lesser-known but equally dramatic three-day experiment, using a pair of mirrors that presented his eyes with a view of his own body from a position in space directly above his head (Figure 2).