declare cupula = difference {
   sphere { 
       <0, 0, 0>
       170
   }
   
   sphere {
		<0, 0, 0>
		165
		}
   
   cylinder {
       <0,-200,175>
       <0,200,175>
       70
   }
   
    cylinder {
       <0,-200,175>
       <0,200,175>
       70
	   rotate 90*y
   }
   
    cylinder {
	   <0,-200,175>
       <0,200,175>
       70
	   rotate -90*y
   }
   
    cylinder {
       <0,-200,175>
       <0,200,175>
       70
	   rotate 180*y
   }
   
   pigment {Blue transmit 1}
	finish { reflection { 0.1 0.8 }}
	interior {	ior 1.5
				fade_distance 5
				fade_power 1.5
				fade_color <0,0,0>
				}
	
		
   translate -2*y
}

object {cupula}