window.onerror=null;
if (document.images) {
  names = new Array("bio", "gallery", "exhibitions", "contact" );
  items = new Array(8);
  for (i=0; i<=7; i++)
     {
	 items[i] = new Image(); }
	 items[0].src = "images/bio_off.gif";
     items[1].src = "images/gallery_off.gif";
     items[2].src = "images/exh_off.gif";
     items[3].src = "images/contact_off.gif";
	
	 items[4].src = "images/bio_on.gif";
     items[5].src = "images/gallery_on.gif";
     items[6].src = "images/exh_on.gif";
     items[7].src = "images/contact_on.gif";
	 }

  function swap(des,num) {
    if (document.images)
      { document.images[names[des]].src = items[num].src; }
  }