Iron mask, collar, leg shackles and spurs used to restrict slaves, 1807 (woodcut)

Illustration from' The penitential tyrant' by Thomas Branagan, a former slave trader turned abollitionist 'Mouth-piece and necklace, the hooks round which are placed to prevent an escapee when pursued in the woods, and to hinder them from laying down the head to procure rest'. 'A flat iron which goes into the mouth, and so effectually keeps down the tongue, that nothing can be swallowed, not even the saliva, a passage for which is made through holes in the mouth-plate'. Leg shackles used on the slave ships; also, 'spurs used on some plantations in Antigua' to prevent escape.