a1 = new Image();
a1.src = "images/bbl.gif";
h1 = new Image();
h1.src = "images/bblh.gif"; 	
a2 = new Image();
a2.src = "images/bhb.gif";     
h2 = new Image();
h2.src  = "images/bhbh.gif";
a3 = new Image();
a3.src = "images/br.gif";     
h3 = new Image();
h3.src  = "images/brh.gif";
a4 = new Image();
a4.src = "images/bo.gif";     
h4 = new Image();
h4.src  = "images/boh.gif"; 	
a5 = new Image();
a5.src = "images/by.gif";     
h5 = new Image();
h5.src  = "images/byh.gif"; 	
a6 = new Image();
a6.src = "images/bg.gif";     
h6 = new Image();
h6.src  = "images/bgh.gif"; 	
function Bildwechsel (Bildnr, Bildobjekt) {
  window.document.images[Bildnr].src = Bildobjekt.src;
}