said retaining {HEAD ~ nut} comprises {TAIL ~ a cylindrical projection extending upstream} at the inner edge of said upstream face of said nut for cooperating with said inwardly facing surface of each of said fly weights, an annular groove in said upstream face of said nut between said cylindrical projection and said conical surface thereof, said groove housing a spring adapted to act axially between said nut and said fly weights, and a collar at the downstream side of said nut cooperating with said radial face of said first shaft 
comprises
said retaining { HEAD ~ nut } comprises { TAIL ~ a cylindrical projection extending upstream } at the inner edge of said upstream face of said nut for cooperating with said inwardly facing surface of each of said fly weights , an annular groove in said upstream face of said nut between said cylindrical projection and said conical surface thereof , said groove housing a spring adapted to act axially between said nut and said fly weights , and a collar at the downstream side of said nut cooperating with said radial face of said first shaft
OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH