{TAIL ~ The number} of vanes 56 may vary but they are preferably spaced between 20 degrees and 30 degrees apart around the circumference of {HEAD ~ the cylindrical wall member} 32 
{ TAIL ~ The number } of vanes 56 may vary but they are preferably spaced between 20 degrees and 30 degrees apart around the circumference of { HEAD ~ the cylindrical wall member } 32
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 HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH