function newImage(arg) {
    if (document.images) {
        rslt = new Image();
        rslt.src = arg;
        return rslt;
    }
}

function changeImages() {
    if (document.images && (preloadFlag == true)) {
        for (var i=0; i<changeImages.arguments.length; i+=2) {
            document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
        }
    }
}

var preloadFlag = false;
function preloadImages() {
    if (document.images) {
        Nav_Bios_over = newImage("images/Nav-Bios-over.gif");
        Nav_Pics_over = newImage("images/Nav-Pics-over.gif");
        Nav_Press_over = newImage("images/Nav-Press-over.gif");
        Nav_Music_over = newImage("images/Nav-Music-over.gif");
        Nav_Schedule_over = newImage("images/Nav-Schedule-over.gif");
        Nav_Contacts_over = newImage("images/Nav-Contacts-over.gif");
        Nav_Links_over = newImage("images/Nav-Links-over.gif");
        preloadFlag = true;
    }
}