The "17 or Glory" on this back of this antique British playing card refers to the 17th Lancers, a cavalry regiment of the British Army, who must at some point have been commemorated with their own deck of cards. The 17th Lancers were raised in 1759 for its participation in the Charge of the Light Brigade during the Crimean War, went on to fight in the American Revolutionary War, the Napoleonic Wars, etc. I am not certain the age of this card, but based on the small (early) indices believe likely 1870s or 80s. I just love the skull and cross bones image, and it's a pretty lovely 4 of spades too with these rich black slightly bleeding spades.
3 9/16" x 2 1/2". Writing in both ink and pencil as well as age toning on the face of the card, but the skull side is in very good shape, bright and clear.