function swapImg(img, source) 
	{
	 document.all(img).src = source;
	}

	function preloader()
	{
   	 for (i = 0; i< image.length; i++)
   	 {
    	  pre_image[i] = new Image();
      	  pre_image[i].src = image[i];
  	 }
	}