Curve C represents {HEAD ~ the amount} of expansion or {TAIL ~ contraction} of fine displacing element 112 from its central position 
of
Curve C represents { HEAD ~ the amount } of expansion or { TAIL ~ contraction } of fine displacing element 112 from its central position
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH