// Script to handle image rollovers on navigation bar.
// If the browser recognises the document.images 
// object, then it can cope with image rollovers.
// Netscape v3.0 or later, MSIE v4.0 or later.

// turn off dodgy error messages

window.onerror = null;

if (document.images) {

// secondary pages
// navigation buttons

   home_on = new Image(90,26);
   home_on.src = "images/nav_home_on.gif";
   home_off = new Image(90,26);
   home_off.src = "images/nav_home.gif";

   contact_on = new Image(44,26);
   contact_on.src = "images/nav_contact_on.gif";
   contact_off = new Image(44,26);
   contact_off.src = "images/nav_contact.gif";

   gallery_on = new Image(86,26);
   gallery_on.src = "images/nav_gallery_on.gif";
   gallery_off = new Image(86,26);
   gallery_off.src = "images/nav_gallery.gif";

   biography_on = new Image(106,26);
   biography_on.src = "images/nav_biography_on.gif";
   biography_off = new Image(106,26);
   biography_off.src = "images/nav_biography.gif";  

   exhibitions_on = new Image(119,26);
   exhibitions_on.src = "images/nav_exhibitions_on.gif";
   exhibitions_off = new Image(119,26);
   exhibitions_off.src = "images/nav_exhibitions.gif";  

   search_on = new Image(122,26);
   search_on.src = "images/nav_search_on.gif";
   search_off = new Image(122,26);
   search_off.src = "images/nav_search.gif";  

   go_on = new Image(33,21);
   go_on.src = "images/nav_go_on.gif";
   go_off = new Image(33,21);
   go_off.src = "images/nav_go.gif";  



}



function navon(imgName) {

   if (document.images) {
      document[imgName].src = eval(imgName + "_on.src");
   }
}

function navoff(imgName) {

   if (document.images) {
      document[imgName].src = eval(imgName + "_off.src");
   }
}