{HEAD ~ A vent} is formed in {TAIL ~ the flask} in such manner as to prevent accidental spillage of liquid therefrom while also permitting entrance of air into the flask when negative internal pressure is applied during removal of liquid therefrom 
is formed in
{ HEAD ~ A vent } is formed in { TAIL ~ the flask } in such manner as to prevent accidental spillage of liquid therefrom while also permitting entrance of air into the flask when negative internal pressure is applied during removal of liquid therefrom
HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH