     }
   
     func execJavascript(message: String) {
+        let measure = Measurement()
         self.webView.evaluateJavaScript(message, completionHandler: { data, error in
             if let err = error {
                 print("jsCallbackError \(err)")

    private var reference: Reference!
    
    func test() {
        let reference = Reference(bibleId: "ERV-SPA.db", bookId: "GEN", chapter: 4)
        self.loadReference(reference: reference)
    }
    

        + "}\n"
    
    static let findVerseNum = "var verseNum = null;\n"
        + "function getClass(startNode, findNode) {\n"
        + "  walkNodes(startNode, findNode);\n"
        + "  return verseNum;\n"
        + "}\n"
        + "function walkNodes(node, findNode) {\n"
        + "  verseNum = findVerseNum(node) || verseNum;\n"
        + "  node = node.firstChild;\n"
        + "  while(node && node !== findNode) {\n"
        + "    walkNodes(node, findNode);\n"
        + "    node = node.nextSibling;\n"
        + "  }\n"
        + "}\n"
