1Separate eggs. Sift the flour, baking powder, and salt together three times.
2In a large mixing bowl, beat yolks until lemon colored. mix in sugar a little at a time. Stir in the lemon extract, vanilla extract and boiling water until smooth. Stir in the flour mixture just until moistened. Whip the egg whites to soft peaks, and fold into the batter.
3Pour the batter into an ungreased 9 inch tube pan. Bake at 350 degrees F ( 175 degrees C) for 45 to 50 minutes. Remove the cake from the oven, and invert the pan over a bottle. Cool and remove from pan.