// Pure Source Code - Another free Service to you from
// www.viewsource.dk, lots of free Java Applets, DHTML and JavaScripts 



<script language="JavaScript">
<!--
var b3=new Image()
var b2=new Image()
var b1=new Image()

b1.src="bg1.jpg";//background image 1
b2.src="bg2.jpg";//background image 2
b3.src="bg3.jpg";//background image 3

var pos=0;

function backhoe()
{
pos=pos+1;
if(pos==4){pos=1;
}
document.body.background=eval("b"+pos+".src");
setTimeout("backhoe()",4000);
}
setTimeout("backhoe()",0);

// -->
</script>