Copy Sortable Item

I have 2 sortable lists, #pieces and #grid. I want to drag items from
#peices and add them to #grid without removing them from #peices. The
current code i have is:
<script type="text/javascript">
    $(function() {
        $("#peices, #grid).sortable({
            connectWith: '.column'
        }).disableSelection();
    });
    </script>
Can someone help me out. cheers for any help!