#declare Ball = 
 sphere{<0,0,0>,0.075 scale <1,1,1> rotate<0,0,0> translate<0,0,0>
	texture{pigment{ color rgb<0.8,1,0>}
                finish { phong 1}}}

union{ //-------------------------------------------------------
 #local Nr = 0;            // start
 #local N_per_Rev = 300;   // number of elements per revolutions
 #local N_of_Rev  = 4.00;  // total number of revolutions 
 #while (Nr < N_per_Rev*N_of_Rev) 
   object{Ball translate<Nr * 0.25/N_per_Rev,0,0>
               rotate<0,Nr * 360/N_per_Rev,0>} 

 #local Nr = Nr + 1;    // next Nr
 #end // ---------------  end of loop 

rotate<-90,0,0>
translate<0,1,-0.5>
} // end of union ----------------------------------------------
