Lemon Champagne Punch
["4 (6 oz.) cans frozen concentrated lemon juice", "4 (6 oz.) cans frozen pineapple juice", "1 1/2 qt. water", "2 qt. ginger ale, chilled", "1 qt. sparkling water, chilled", "1 bottle (4/5 qt.) dry champagne, chilled"]
["Mix juices and water.", "Chill, covered.", "Before serving, add ginger ale and sparkling water and pour over ice cubes in punch bowl.", "Pour chilled champagne over punch and stir gently. Yields 50 servings."]
["lemon juice", "pineapple juice", "water", "ginger ale", "sparkling water", "champagne"]