The machine includes {HEAD ~ a rotatable drum} having {TAIL ~ a spaced pair} of cylindrically contoured surfaces 
The machine includes { HEAD ~ a rotatable drum } having { TAIL ~ a spaced pair } of cylindrically contoured surfaces
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH