window.onload = function() {
    initGallery();
    }

  function initGallery() {
    if (!document.getElementsByTagName) return false;
    if (!document.getElementById) return false;
    if (!document.getElementById("gallery")) return false;
    var gallery = document.getElementById("gallery");
    var links = gallery.getElementsByTagName("a");
    for ( var i=0; i < links.length; i++) {
      links[i].onclick = function() {
        return showPic(this);
      }
    }
  }

  function showPic(whichpic) {
    if(!document.getElementById("pic")) alert("first break");
    var source = whichpic.getAttribute("href");
    var pic = document.getElementById("pic");
    if (pic.nodeName != "IMG") return true;
    pic.setAttribute("src", source);
    if (!document.getElementById("caption")) return false;
    var text = whichpic.getAttribute("title") ? whichpic.getAttribute("title") : "";
    var caption = document.getElementById("caption");
    if (caption.firstChild.nodeType == 3) {
      caption.firstChild.nodeValue = text;
    }
    return false;
  }