if (document.images) {

  image1on = new Image();
  image1on.src = "images/nav/home_on.gif";
  
  image2on = new Image();
  image2on.src = "images/nav/stock_on.gif";

  image3on = new Image();
  image3on.src = "images/nav/family_on.gif";

  image4on = new Image();
  image4on.src = "images/nav/advertising_on.gif";

  image5on = new Image();
  image5on.src = "images/nav/weddings_on.gif";
  
  image6on = new Image();
  image6on.src = "images/nav/architectural_on.gif";

  image7on = new Image();
  image7on.src = "images/nav/location_on.gif";

  image8on = new Image();
  image8on.src = "images/nav/brochure_on.gif";

  image9on = new Image();
  image9on.src = "images/nav/order_on.gif";
  
  image10on = new Image();
  image10on.src = "images/nav/weekly_on.gif";

  image11on = new Image();
  image11on.src = "images/nav/buy_on.gif";

  image12on = new Image();
  image12on.src = "images/nav/downtown_on.gif";

  image13on = new Image();
  image13on.src = "images/nav/address_on.gif";

  image14on = new Image();
  image14on.src = "images/nav/virtualtours_on.gif";

  image15on = new Image();
  image15on.src = "images/nav/book_on.gif";

  image1off = new Image();
  image1off.src = "images/nav/home_off.gif";
  
  image2off = new Image();
  image2off.src = "images/nav/stock_off.gif";
  
  image3off = new Image();
  image3off.src = "images/nav/family_off.gif";
  
  image4off = new Image();
  image4off.src = "images/nav/advertising_off.gif";
  
  image5off = new Image();
  image5off.src = "images/nav/weddings_off.gif";
  
  image6off = new Image();
  image6off.src = "images/nav/architectural_off.gif";
  
  image7off = new Image();
  image7off.src = "images/nav/location_off.gif";
  
  image8off = new Image();
  image8off.src = "images/nav/brochure_off.gif";
  
  image9off = new Image();
  image9off.src = "images/nav/order_off.gif";
  
  image10off = new Image();
  image10off.src = "images/nav/weekly_off.gif";
  
  image11off = new Image();
  image11off.src = "images/nav/buy_off.gif";
  
  image12off = new Image();
  image12off.src = "images/nav/downtown_off.gif";
  
  image13off = new Image();
  image13off.src = "images/nav/address_off.gif";
  
  image14off = new Image();
  image14off.src = "images/nav/virtualtours_off.gif";
  
  image15off = new Image();
  image15off.src = "images/nav/book_off.gif";
  
}
function turnOn(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "on.src");
  }
}

function turnOff(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "off.src");
  }
}