var preloaded = [];

  for (var i = 1; i <= 7; i++) {
   preloaded[i] = [loadImage(i + "-0.gif"), loadImage(i + "-1.gif")];
  }

  function init() {

   if (mtDropDown.isSupported()) {
    mtDropDown.initialize();
      }
  }

  function loadImage(sFilename) {
   var img = new Image();
   img.src ="images/" + sFilename;
   return img;
  }

  function swapImage(imgName, sFilename) {
   document.images[imgName].src = sFilename;
  }