Pare and cut watermelon rind into pieces 2" long and 3/4" wide. Cover with brine made by dissolving 1 tablespoon salt in 1 quart water. Let stand overnight; drain. Cover with water and boil 10 minutes; drain. Cover with a heavy syrup made of 1 part sugar and 1 part water. Add 1 thinly sliced lemon to each 3 quart rind. Add whole spices if desired. Cook slowly until rind is tender and clear.