Joseph Mortimer Granville (1833–1900) was an English Doctor, Author and Inventor. In the late 1880s Granville invented the electric vibrator, a handheld battery operated device designed to relieve more muscle aches and pains. Originally called a percusser or more colloquially "Granville's hammer", the machine was manufactured and sold to physicians, many of whom used the equipment to create "hysterical paroxysm" in their patients with female hysteria.
As vibrators began to be used for bringing hysterical women to paroxysm, its inventor tried to disassociate himself from the device's "mis-use". In his 1883 book on his research, Nerve-Vibration and Excitation as Agents in the Treatment of Functional Disorder and Organic Disease, he wrote, "I have never yet percussed a female patient ... I have avoided, and shall continue to avoid the treatment of women by percussion, simply because I do not wish to be hoodwinked, and help to mislead others, by the vagaries of the hysterical state ..."
Granville was portrayed by actor Hugh Dancy in the 2011 film Hysteria.