function randomBannerImg() {
	var numImages = 4;
	var i = Math.round(numImages*Math.random());
	/*var i = i+ 1;*/
		
	var bannerDiv = document.getElementById("banner");
	var bannerImg = document.createElement("img");
	bannerImg.setAttribute("src", "http://west.stanford.edu/uiparts/home/banner/" + i + ".jpg");
	bannerImg.setAttribute("alt","Bill Lane Header Images");
	bannerImg.className = ("image_banner");
	bannerImg.setAttribute("border","0");
	bannerDiv.appendChild(bannerImg);
	}