function archive_toggle_visible(id)
{

  var elem = document.getElementById(id);
  var elem_arrow = document.getElementById(id + '_arrow');

  if (elem.style.visibility == "visible"){
    elem_arrow.innerHTML = "⇨";
    elem.style.visibility = "hidden";
    elem.style.display = "none";
  }
  else {
    elem_arrow.innerHTML = "⇩";
    elem.style.visibility = "visible";
    elem.style.display = "block";
  }
}