The blades of the second row are shaped so as to produce {HEAD ~ a uniform blood flow} along {TAIL ~ the trailing edges} of the blades 
along
The blades of the second row are shaped so as to produce { HEAD ~ a uniform blood flow } along { TAIL ~ the trailing edges } of the blades
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH