In a pitcher, combine pineapple juice, fresh lemon juice and orgeat. Stir well. Transfer to an empty glass liquor bottle. (There will be 1 cup leftover.) Chill the bottle.
When ready to serve, shake well in the bottle and pour over ice (preferably pebble ice) in a highball. Slowly pour 1 1/2 ounces Empress Gin over the top.
Serve with a straw and garnish with a fresh orchid or pineapple.
Makes about 6 drinks.