I mean the water, and sometimes some of the EG, turns into vapor in the form of very small bubbles.  I have never heard of expiation but that may very well be the correct jargon.  Here is the definition I found:

 

expiation (noun) -
	1. the act of atoning for sin or wrongdoing (especially appeasing a deity) Synonyms:  atonement, propitiation 2. compensation for a wrong "we were unable to get satisfaction from the local store" Synonyms:  atonement, satisfaction

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Dave Leonard
Turbo Rotary RV-6 N4VY
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