The “shock” experienced by touching certain fish (electric fish) is described in ancient Egyptian texts dating from 2750 BC.1 Arab physicians attempted to provide relief from pain of gout and headaches by instructing patients to touch these fish in the expectation that the energy thus transferred would cure them of their ailment. The first study of electricity applied to the eye was in 1855 by the Frenchman B Duchenne. He noted that a continuous application of 1.4 milliamps of current to the eye affected light and colour …