Sexual armour patent, 1908. Artwork of a device invented by American nurse Ellen E. Perkins. It was designed to be worn by male and female asylum patients to prevent masturbation. The armour was made from a cloth based body suit and featured a metal crotch (seen here in side view) that could only be opened using a key. The artwork shows how the crotch flap opened (dotted lines) could open. The front portion of the crotch flap was perforated (lower right) to allow passage of urine. Masturbation was considered by some at the time to be one of the causes of insanity. See image C024/3620 for full design.