var delay = 8000;
var timer;
for(var i=0;i<pics.length;i++) {
    var tmp = "/images/"+pics[i];
    pics[i] = new Image();
    pics[i].src = tmp;
}
function show(i) {
    if(document.images && pics.length>1 && i<=pics.length) {
        clearTimeout(timer);
        if(i>=pics.length)
            timer = setTimeout("show(1)",delay);
        else
            timer = setTimeout("show("+(i+1)+")",delay);
        document.getElementById('pic').src = pics[i].src;
    }
}
if(pics.length>1)
    timer = setTimeout("show(2)",delay);