Fading image using jquery FadeTo

<script src="Scripts/jquery-1.7.min.js" type="text/javascript"></script>
<script>
window.setInterval("Method()", 1000);
Method = function () {
var ff = parseFloat($("img").css("opacity")).toFixed(1);
// alert(ff);
if (ff == 0.6)
$("img").fadeTo("slow", 1);
else
$("img").fadeTo("slow", 0.6);
};
</script>


<img border="0" src="Images/Bald.jpg" width="400" />