if (document.images)
    {
      preload_image_object = new Image();
      // set image url
      image_url = new Array();
      image_url[0] = "../images/header.jpg";
      image_url[1] = "../images/footer.jpg";
      image_url[2] = "../images/dutchsml.jpg";
      image_url[3] = "../images/robert.jpg";
		image_url[4] = "../images/robert_spider1.jpg";
		image_url[5] = "../images/robert_spider2.jpg";
		image_url[6] = "../images/robert_spider3.jpg";
		image_url[7] = "../images/robert_spider4.jpg";
		image_url[8] = "../images/robert_spider5.jpg";
		image_url[9] = "../images/robert_spider6.jpg";
		
       var i = 0;
       for(i=0; i<=2; i++) 
         preload_image_object.src = image_url[i];
    }