I filmed this video last summer in Gettysburg and never got around to editing it and uploading until now. In the video the soldier is showing us how to play Faro which is a period card game.
According to Wikipedia, Faro came to the US in the 19th century to become the most widespread and popularly favored gambling game. The article goes on to say that it was also easy to cheat at the game. The betting layout consists of a suit of cards, from Ace up to King. From there, players will bet on the card rank of their choice. The dealer then turns over cards in pairs, a winner and a loser, and pays out or collects accordingly.
Here is the video of the soldier’s teaching us about Faro: