One method of measuring the resiliency of a ball at impact is to utilize an air cannon or {HEAD ~ other means} of propelling {TAIL ~ a ball} at velocities equivalent to those of a golf club head 
of propelling
One method of measuring the resiliency of a ball at impact is to utilize an air cannon or { HEAD ~ other means } of propelling { TAIL ~ a ball } at velocities equivalent to those of a golf club head
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH