function preLoad()
{
  iPath= 'images/';  iExt= 'png';

  if(document.images)
  {
    var argLen = arguments.length;
    for(var i = 0; i < argLen; i++)
    {
      var arg = arguments[i];
      self[arg] = new Image();
      self[arg].src = iPath + arg + '.' + iExt;
    }
  }
}