function swapImage(url) {
  var container = $('#exhibition_image');
  var ei = container.get(0);

  var e = document.createElement('img');
  e.src = url;

  if (ei.childNodes.length > 0) {
    ei.replaceChild(e, ei.firstChild);
  } else {
    ei.appendChild(e);
  }

  $('#exhibition_image img').show();
}

function resetImage() {
  $('#exhibition_image img').hide();
}