Gumpower

• power

• gumption

• gum: sticky substance applied to the back of a stamp, or to the flap of an envelope, to affix and/or seal them

• gum power: the ability to chew.

• gunpowder
  • according to Samuel Lover's 1841 novel Handy Andy, gunpowder was once sold in Irish post offices
  • there are possible allusions here to the Gunpowder Plot of 1605 (in which a King was to be deposed and his offspring installed in his place) and/or to the Easter Rising of 1916 (which also sought to depose a monarchy, and was centered around the Dublin General Post Office)