History In Britain's Forgotten Slave Owners, David Olusoga describes the legacy of cruelty which underpins our wealth. In one sequence during the first episode whilst visiting Jamaica he's confronted with the instruments of torture utilised to subjugate slaves. There's a clip of this sequence here and amongst the objects is this tongue restraint utilised to subjugate slaves who challenged authority.
The apparatus looked familiar and for the rest of the sequence I asked myself where I'd seen it before. Then I remembered.
In Suffragettes Forever! The Story of Women and Power, Amanda Vickery describes the history of the women's suffrage movement. In one sequence during the first episode whilst visiting the Lancaster Castle Museum she's confronted by this tongue restraint utilised to subjugate women who challenged authority.