if (document.images) {
var oneon = new Image(10, 25);
oneon.src = "media/arrow_on.jpg";
var oneoff = new Image(10, 25);
oneoff.src = "media/arrow_off.jpg";

var twoon = new Image(10, 25);
twoon.src = "media/arrow_on.jpg";
var twooff = new Image(10, 25);
twooff.src = "media/arrow_off.jpg";

var threeon = new Image(10, 25);
threeon.src = "media/arrow_on.jpg";
var threeoff = new Image(10, 25);
threeoff.src = "media/arrow_off.jpg";

var fouron = new Image(10, 25);
fouron.src = "media/arrow_on.jpg";
var fouroff = new Image(10, 25);
fouroff.src = "media/arrow_off.jpg";

var fiveon = new Image(10, 25);
fiveon.src = "media/arrow_on.jpg";
var fiveoff = new Image(10, 25);
fiveoff.src = "media/arrow_off.jpg";

var sixon = new Image(10, 25);
sixon.src = "media/arrow_on.jpg";
var sixoff = new Image(10, 25);
sixoff.src = "media/arrow_off.jpg";

var sevenon = new Image(10, 25);
sevenon.src = "media/arrow_on.jpg";
var sevenoff = new Image(10, 25);
sevenoff.src = "media/arrow_off.jpg";

var eighton = new Image(10, 25);
eighton.src = "media/arrow_on.jpg";
var eightoff = new Image(10, 25);
eightoff.src = "media/arrow_off.jpg";}

function img_act(imgName){
if (document.images) {
imgOn = eval(imgName + "on.src");
document [imgName].src = imgOn;}
}

function img_inact(imgName){
if (document.images) {
imgOff = eval(imgName + "off.src");
document [imgName].src = imgOff;}
}