if (document.images) {
  image1on = new Image();
  image1on.src = "nav/gallery-on.gif";
  image1off = new Image();
  image1off.src = "nav/gallery-off.gif";

  image2on = new Image();
  image2on.src = "nav/collections-on.gif";
  image2off = new Image();
  image2off.src = "nav/collections-off.gif";
  /*
  image2on = new Image();
  image2on.src = "images/about_on.gif";
  image2off = new Image();
  image2off.src = "images/about_off.gif";
  image3on = new Image();
  image3on.src = "images/contact_on.gif";
  image3off = new Image();
  image3off.src = "images/contact_off.gif";
*/
  image4on = new Image();
  image4on.src = "images/arrow_left_on.gif";
  image4off = new Image();
  image4off.src = "images/arrow_left_off.gif";
  image5on = new Image();
  image5on.src = "images/arrow_right_on.gif";
  image5off = new Image();
  image5off.src = "images/arrow_right_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');
  }
}

function turnOffAll() {
  if (document.images) {
    document.image2.src = image2off.src;
/*    document.image1.src = image1off.src;
    document.image9.src = image9off.src;*/
//    document.image4.src = image4off.src;
  }
}