function getAppVersion()
                {
                appname= navigator.appName;
                appversion = navigator.appVersion;
                majorver = appversion.substring(0, 1);
                if ( (appname == "Netscape") && ( majorver >= 3 ) ) return 1;
                if ( (appname == "Microsoft Internet Explorer") && (majorver >= 4) ) return 1;
        return 0;
                }

function swtch(num, imgname) {
  if (getAppVersion()) {
 document[imgname].src = img[num].src;
}
}

imgsrc = new Array();
imgsrc[0] = "img/aki01.gif";
imgsrc[1] = "mori_img/kou02.gif";
imgsrc[2] = "mori_img/kou01.gif";
imgsrc[3] = "mori_img/gyou02.gif";
imgsrc[4] = "mori_img/gyou01.gif";
imgsrc[5] = "mori_img/kyou02.gif";
imgsrc[6] = "mori_img/kyou01.gif";
imgsrc[7] = "mori_img/map02.gif";
imgsrc[8] = "mori_img/map01.gif";
imgsrc[9] = "mori_img/info02.gif";
imgsrc[10] = "mori_img/info01.gif";
imgsrc[11] = "mori_img/gyou02b.gif";
imgsrc[12] = "mori_img/gyou01b.gif";
imgsrc[13] = "mori_img/info03b.gif";
imgsrc[14] = "mori_img/info03a.gif";
imgsrc[15] = "mori_img/info04b.gif";
imgsrc[16] = "mori_img/info04a.gif";
imgsrc[17] = "mori_img/top02.gif";
imgsrc[18] = "mori_img/top01.gif";
imgsrc[19] = "ill-img/ill1a.gif";
imgsrc[20] = "ill-img/ill2b.gif";
imgsrc[21] = "ill-img/ill2a.gif";
imgsrc[22] = "ill-img/ill3b.gif";
imgsrc[23] = "ill-img/ill3a.gif";
imgsrc[24] = "ill-img/ill4b.gif";
imgsrc[25] = "ill-img/ill4a.gif";
imgsrc[26] = "ill-img/ill5b.gif";
imgsrc[27] = "ill-img/ill5a.gif";
imgsrc[28] = "ill-img/ill5c.gif";
imgsrc[29] = "zu-img/zu1a.jpg";
imgsrc[30] = "zu-img/zu1b.gif";
imgsrc[31] = "zu-img/zu1c.gif";
imgsrc[32] = "zu-img/zu1e.gif";
imgsrc[33] = "zu-img/zu2a.jpg";
imgsrc[34] = "zu-img/zu2b.gif";
imgsrc[35] = "zu-img/zu1d.gif";
imgsrc[36] = "zu-img/zu2c.gif";

if (getAppVersion())
                {
        img = new Array();
        for (i = 0; i < imgsrc.length; i++)
                                {
                img[i] = new Image();
                img[i].src = imgsrc[i];
                        }
                }