From Historic England entry:
“GV II Pillar box of the Penfold type, c1866-79. Cast-iron. Hexagonal plan on moulded base. Door with initial VR and moulded frame for collection times. Royal arms above the mouth flanked by words “Post” and “Office”. Hexagonal domed lid with beaded cornice and foliated dome. No longer in use.
In 1914 the pillar box was damaged by militant suffragettes from the Women’s Social and Political Union (WSPU), the group founded by Emmeline Pankhurst in 1903 which used direct actions in its campaign for votes for women. In November 1911 Emily Wilding Davison became the first suffragette to attempt to set fire to a pillar box, and over the next three years suffragettes attacked pillar boxes throughout Britain using paraffin-soaked rags, corrosive liquids, ink and incendiary bombs, in order to destroy the mail inside. Attacks were often carried out at night and the perpetrators were rarely caught. On 9 January 1914 smoke was seen coming from this box; when opened it was discovered that tar and oil had been poured in and set alight, badly damaging the contents. A message referring to suffragette prisoners was found, alluding to the culprits.”