The 19th-century distaste for non-reproductive sex led to some terrifying inventions. A steel anti-masturbation device, dated from 1880-1920, was designed to be fitted to a penis at night “to prevent loss of fluids through wet dreams”, as a number of sexologists at the time thought to loss of sperm through nocturnal emissions was a serious problem. The small circular device, below, is designed to prevent masturbation while the 1946 medical work The Secret Companion by R J Brodie charted the negative effects of self love – a “wanton waste” of semen was said to cause disorders from nervousness to paralysis.