In a second embodiment, {HEAD ~ a pair} of holes are formed through {TAIL ~ the base plate} of one of the scroll members 
are formed through
In a second embodiment , { HEAD ~ a pair } of holes are formed through { TAIL ~ the base plate } of one of the scroll members
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH