if (document.getElementById) { window.onload = swap };
					
function swap() {
	var numimages=2;
	rndimg = new Array("images/topview/1.gif", "images/topview/2.gif"); 
	ximagepick=(Math.floor(Math.random()*numimages));
	randomimage=(rndimg[ximagepick]);
	document.getElementById("topimage").style.backgroundImage = "url("+ randomimage +")"; 
	}