This eliminates false readings due to {TAIL ~ downwardly descending soap film solution} on {HEAD ~ the inside} or the outside of tube 22 
This eliminates false readings due to { TAIL ~ downwardly descending soap film solution } on { HEAD ~ the inside } or the outside of tube 22
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH