var image="";
var banners=0;
function cycle() {
  if (++banners > 18) banners=1;
    loadbanners();
    document.banner1.src = image;
    window.setTimeout('cycle();',2000);
  }
function loadbanners() {
   if (banners==1)
      {
      image="images/banner_1_tn.gif";
      }
   if (banners==2)
      {
      image="images/banner_2_tn.gif";
      }
   if (banners==3)
      {
      image="images/banner_3_tn.gif";
      }
   if (banners==4)
      {
      image="images/banner_4_tn.gif";
      }
   if (banners==5)
      {
      image="images/banner_5_tn.jpg";
      }
   if (banners==6)
      {
      image="images/banner_6_tn.gif";
      }
   if (banners==7)
      {
      image="images/banner_7_tn.gif";
      }
   if (banners==8)
      {
      image="images/banner_8_tn.gif";
      }
   if (banners==9)
      {
      image="images/banner_9_tn.gif";
      }
   if (banners==10)
      {
      image="images/banner_10_tn.gif";
      }
   if (banners==11)
      {
      image="images/banner_11_tn.gif";
      }
   if (banners==12)
      {
      image="images/banner_12_tn.gif";
      }
   if (banners==13)
      {
      image="images/banner_13_tn.jpg";
      }
   if (banners==14)
      {
      image="images/banner_14_tn.jpg";
      }
   if (banners==15)
      {
      image="images/banner_15_tn.jpg";
      }
   if (banners==16)
      {
      image="images/banner_16_tn.jpg";
      }
   if (banners==17)
      {
      image="images/banner_17_tn.gif";
      }
   if (banners==18)
      {
      image="images/banner_18_tn.gif";
      }
   
}