function loadimg(imgname){

if (document.images) (new Image()).src = imgname;}

loadimg("images/navi01h.gif");
loadimg("images/navi02h.gif");
loadimg("images/navi03h.gif");
loadimg("images/navi04h.gif");
loadimg("images/navi05h.gif");
loadimg("images/navi06h.gif");
loadimg("images/navi07h.gif");
loadimg("images/top01h.gif");
loadimg("images/top02h.gif");
loadimg("images/book01h.gif");
loadimg("images/book02h.gif");
loadimg("images/book03h.gif");
loadimg("images/book04h.gif");