function showAll() {
    var imgs = document.images;
    for (var i = 0; i < imgs.length; i++) {
        if (imgs[i].className == "thumb") {
            if (imgs[i].style.visibility == "hidden") {
	  			if (imgs[i].style.removeAttribute) imgs[i].style.removeAttribute("visibility");
       			else imgs[i].style.removeProperty("visibility");
            }
            else imgs[i].style.visibility = "hidden";
        }
    }
}