A Pound of Retention

Jun 28, 2014

RAY: Sometime in the late 1930s, German and perhaps other countries' aeronautical engineers were working on a device which did the following: It took water vapor, which is one of the products of gasoline engine combustion, and would condense it into water and save it.

“Not such a big deal,” you say. Well, it would save it in an interesting way. It would save it in such a way that the amount of water saved would be exactly the equivalent in weight to the amount of fuel that the engine burned. So as the engine burned a pound of fuel it would save a pound of water and discard the rest. Why would you want to do this?

RAY: So as the engine burned a pound of fuel, a pound of water would be saved, and the rest would be discarded, of course. The question is why would you want to do this.

TOM: Oh, dirigibles!

RAY: Exactly. At that time they had switched their dirigibles over from hydrogen as the levitating medium, which was a little dangerous, to helium -- which was much safer, but very expensive. And needless to say, as you consume fuel and the craft becomes lighter and lighter, you have to spew the stuff out, but you can't do that because it's expensive. So, you what you want to do is save some of the by-products, so you keep the weight of the vehicle the same. So who’s our winner?

TOM: The winner is Melissa Glasser from Marion, Iowa. Congratulations!

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