How do I get this javascript to run every second?

source code:

<script type="text/javascript">

$(function() {

    //More Button

    $('.more').live("click",function()  {

        var ID = $(this).attr("id");

        if(ID) {

            $("#more"+ID).html('<img src="moreajax.gif" />');



            $.ajax({

                type: "POST",

                url: "ajax_more.php",

                data: "lastmsg="+ ID, 

                cache: false,

                success: function(html){

                    $("ol#updates").prepend(html);

                    $("#more"+ID).remove();

                }

            });

        } else {

            $(".morebox").html('no posts to display');

        }



        return false;



    });

});



</script>