//------------------------------------------ 
#declare Ball = 
 sphere{ <0,0,0>,0.5 
         scale <1,1,1> rotate<0,0,0> translate<0,0,0>
	 texture{ pigment{ color rgb<1,0,0>}
                  finish { phong 1}
                }
       } //---------------------------------

union{ //-----------------------------------
 #local Nr = 0;     // start
 #local EndNr = 10; // end
 #while (Nr< EndNr) 

   object{ Ball translate<0,0,Nr*1.5>} 

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

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