receiving data fixed the problem.
With this
$("#ThumbNails").bind("tap", function (html) {
lastShown = CurrentPage;
PopulateThumbsEx(BookID, lastShown);
$("#book").fadeOut("fast");
$(".ThumbNailNav").fadeIn(500);
$("#thumbimg").append(html).prepend(thumbnails);
$("#thumbimg").fadeIn(1000);
});