var header = new Array();
  header[1]="images/MFCVipersWebsiteHeader1.png";
  header[2]="images/MFCVipersWebsiteHeader2.png";

var img = new Image();
  

  
function get_header() {
  var rand_no=2
  var x = Math.ceil(rand_no*Math.random())
  img.src = header[x];
  document.header.src=img.src;
}
window.onload=get_header;