A difference in {HEAD ~ alkali metal vapor pressure} on {TAIL ~ the opposite sides} of electrolyte tube 14 results in the creation of a difference in electrical potential across the electrolyte 
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A difference in { HEAD ~ alkali metal vapor pressure } on { TAIL ~ the opposite sides } of electrolyte tube 14 results in the creation of a difference in electrical potential across the electrolyte
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH