JQuery script not working in firefox

JQuery script not working in firefox

<script type="text/javascript"
src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script type="text/javascript" src="jquery.easing.1.3.js"></script>
<script type="text/javascript">
$(function() {
$('ul.nav a').bind('click',function(event){
var $anchor = $(this);
/*
if you want to use one of the easing effects:
$('html, body').stop().animate({
scrollLeft: $($anchor.attr('href')).offset().left
}, 1500,'easeInOutExpo');
*/
$('html, body').stop().animate({
scrollLeft: $($anchor.attr('href')).offset().left
}, 1000);
event.preventDefault();
});
});
</script>