Baking powder.

Just a short note about baking powder.  I had always thought that it must somehow be related to baking soda and my suspicions were confirmed: it is a combination of baking soda, corn starch and cream of tartar.  I promised myself that the next time I ran out I would make my own and today I did, using 1/4 cup of baking soda, 2 tbsp cream of tartar and 2 tbsp corn starch.  I just used my old baking powder container.  I'm never buying baking powder again!