var img1 = new Image();

var img2 = new Image();
var img2_1 = new Image();
var img2_2 = new Image();
var img2_3 = new Image();
var img2_4 = new Image();
var img2_3a = new Image();
var img2_3b = new Image();
var img2_3c = new Image();

var img3 = new Image();
var img3_1 = new Image();
var img3_2 = new Image();
var img3_3 = new Image();

var img4 = new Image();
var img4_1 = new Image();
var img4_2 = new Image();
var img4_3 = new Image();

var img5 = new Image();
var img5_1 = new Image();
var img5_2 = new Image();
var img5_3 = new Image();
var img5_4 = new Image();

var img6 = new Image();
var img7 = new Image();
var img8 = new Image();
var img9 = new Image();

img1.src="http://www.blacher.de/images/nav/top_index.jpg"

img2.src="http://www.blacher.de/images/nav/img2.jpg"
img2_1.src="http://www.blacher.de/images/nav/img2_1.jpg"
img2_2.src="http://www.blacher.de/images/nav/img2_2.jpg"
img2_3.src="http://www.blacher.de/images/nav/img2_3.jpg"
img2_4.src="http://www.blacher.de/images/nav/img2_4.jpg"
img2_3a.src="http://www.blacher.de/images/nav/img2_3a.jpg"
img2_3b.src="http://www.blacher.de/images/nav/img2_3b.jpg"
img2_3c.src="http://www.blacher.de/images/nav/img2_3c.jpg"

img3.src="http://www.blacher.de/images/nav/img3.jpg"
img3_1.src="http://www.blacher.de/images/nav/img3_1.jpg"
img3_2.src="http://www.blacher.de/images/nav/img3_2.jpg"
img3_3.src="http://www.blacher.de/images/nav/img3_3.jpg"

img4.src="http://www.blacher.de/images/nav/img4.jpg"
img4_1.src="http://www.blacher.de/images/nav/img4_1.jpg"
img4_2.src="http://www.blacher.de/images/nav/img4_2.jpg"
img4_3.src="http://www.blacher.de/images/nav/img4_3.jpg"

img5.src="http://www.blacher.de/images/nav/img5.jpg"
img5_1.src="http://www.blacher.de/images/nav/img5_1.jpg"
img5_2.src="http://www.blacher.de/images/nav/img5_2.jpg"
img5_3.src="http://www.blacher.de/images/nav/img5_3.jpg"

img6.src="http://www.blacher.de/images/nav/img6.jpg"
img7.src="http://www.blacher.de/images/nav/img7.jpg"
img8.src="http://www.blacher.de/images/nav/img8.jpg"
img9.src="http://www.blacher.de/images/nav/img9.jpg"

if(navigator.userAgent.indexOf("MSIE")==-1 && parseInt(navigator.appVersion) <= 4){
wechsel = false;
} else {
wechsel = true;
}

function bw(Bild)
  {
if(wechsel == true) {
 window.document.images[0].src = Bild.src;
  } 
  }