The game itself is difficult to find these days. However any Starnet online casino offers the game.
All cards are ranked as in poker, the suit is irrelevant, and aces are always high.
First the player places a wager. Then the dealer places two cards on the table face up. If the two cards are consecutive then the hand is a push. If the two cards are neither consecutive nor equal the dealer announces the spread, or the number of card values in between the cards. For example a 5 and 10 would have a spread of 4.