Kellogg's Submarine

 I remember having one of these plastic submarines when I was a kid.  Probably it was from a box of Frosted Flakes, one of my favorites.

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But just recently I realized why the toy was a dud in my eyes.  It was supposed to go up and down in the water by itself, see:

https://en.wikipedia.org/wiki/Baking_powder_submarine

also see:

http://torgo.org/bpsubs/

It was patented (2712710):

My sub didn't work right.  I put in the powder, put in the plug, placed the sub in a bathtub of water and nothing happened.  In 2023 I finally realized that it was because I had used baking soda rather than baking powder.  Baking powder has an acid and a base mixed together in dry form.  When water is added CO2 gas is emitted - that's what causes the sub to move (also the pancakes to rise).  Baking soda does nothing fun when in contact with water - it just dissolves.  One other problem was that I eventually lost the little metal plug somewhere along the way that held the baking powder in place.

A 60 year old mystery finally solved, you never see Sherlock Holmes or Dr. Watson solve real mysteries like this !

Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm