var preloadFlag = false;
function newImage(arg) {
   if (document.images) {
      rslt = new Image();
      rslt.src = arg;
      return rslt;
   }
}
function changeImages() {
   if (document.images && (preloadFlag == true)) {
      for (var i=0; i<changeImages.arguments.length; i+=2) {
         document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
      }
   }
}
function preloadImages() {
   if (document.images) {
      hm_top_03_o = newImage("media/hm_top_03_o.jpg");
      hm_top_05_o = newImage("media/hm_top_05_o.jpg");
      hm_top_07_o = newImage("media/hm_top_07_o.jpg");
      map_02_o = newImage("media/map_02_o.gif");
      map_04_o = newImage("media/map_04_o.gif");
      map_05_o = newImage("media/map_05_o.gif");
      map_08_o = newImage("media/map_08_o.gif");
      map_10_map_05_o = newImage("media/map_10_map_05_o.gif");
      map_12_o = newImage("media/map_12_o.gif");
      map_15_o = newImage("media/map_15_o.gif");
      map_19_o = newImage("media/map_19_o.gif");
      preloadFlag = true;
   }
}