if (document.images) {
    // "On" images
    img01on = new Image(); img01on.src = "images/tour_on.png";
    img02on = new Image(); img02on.src = "images/archive_on.png";
    img03on = new Image(); img03on.src = "images/news_on.png";
    img04on = new Image(); img04on.src = "images/whatson_on.png";
    img05on = new Image(); img05on.src = "images/facilities_on.png";
    img06on = new Image(); img06on.src = "images/map_on.png";
    img07on = new Image(); img07on.src = "images/technical_on.png";
    img08on = new Image(); img08on.src = "images/farm_on.png";
    img09on = new Image(); img09on.src = "images/workshop_on.png";
    img10on = new Image(); img10on.src = "images/whoarewe_on.png";
    img11on = new Image(); img11on.src = "images/membership_on.png";
    img12on = new Image(); img12on.src = "images/history_on.png";
    img13on = new Image(); img13on.src = "images/links_on.png";
    img14on = new Image(); img14on.src = "images/contact_on.png";
    img15on = new Image(); img15on.src = "images/whatsnext_on.png";
    img16on = new Image(); img16on.src = "images/donations_on.png";
    img17on = new Image(); img17on.src = "images/education_on.png";

	// "Off" images
    img01off = new Image(); img01off.src = "images/tour_off.png";
    img02off = new Image(); img02off.src = "images/archive_off.png";
    img03off = new Image(); img03off.src = "images/news_off.png";
    img04off = new Image(); img04off.src = "images/whatson_off.png";
    img05off = new Image(); img05off.src = "images/facilities_off.png";
    img06off = new Image(); img06off.src = "images/map_off.png";
    img07off = new Image(); img07off.src = "images/technical_off.png";
    img08off = new Image(); img08off.src = "images/farm_off.png";
    img09off = new Image(); img09off.src = "images/workshop_off.png";
    img10off = new Image(); img10off.src = "images/whoarewe_off.png";
    img11off = new Image(); img11off.src = "images/membership_off.png";
    img12off = new Image(); img12off.src = "images/history_off.png";
    img13off = new Image(); img13off.src = "images/links_off.png";
    img14off = new Image(); img14off.src = "images/contact_off.png";
    img15off = new Image(); img15off.src = "images/whatsnext_off.png";
    img16off = new Image(); img16off.src = "images/donations_off.png";
    img17off = new Image(); img17off.src = "images/education_off.png";

  }
  function imgOn(imgName) {
    if (document.images) {
        document.images[imgName].src = eval(imgName + "on.src");
    }
  }
  function imgOff(imgName) {
      if (document.images) {
          document.images[imgName].src = eval(imgName + "off.src");
      }
  }