Preconcerted Code Words Used by Secretary of Mary, Queen of Scots

Mary, Queen of Scots, is known to have used various ciphers, including very simple ones as well as ones with quite a few code symbols. I recently learned Gilbert Curll, her Scottish secretary, also used preconcerted language (code words) such as "the merchant of London" (Queen of England). I added it to "Ciphers of Mary, Queen of Scots".