///sor Surface of Revolution 
sor{
  7,
  <0.306,-0.140>,
  <0.605,-0.030>,
  <0.688, 0.341>,
  <0.313, 0.547>,
  <0.165, 0.894>,
  <0.265, 1.000>,
  <0.748, 1.215>

  //  sturm  // optional!
     texture { pigment{ color rgb<0.6,0.5,1>}
               // normal { bumps 0.75 scale 0.010}
               finish { phong 1}
             } // end of texture 
     scale 1.0  rotate<0,0,0> translate<0,0,0>
   } // end of sor ----------------------------------