Description from the Publisher
In Solitaire Tower, cards are arranged in 7 columns of 5 cards each. The lowest card in each column can be moved to the foundation if it has a value that is either one greater than or one less than the card showing in the foundation. If no card is currently in the foundation, any of the lowest cards in the columns may be moved. If you are unable to move a card from the column, you may take another card from the deck and move it to the foundation.