var bbon=new Image();
bbon.src="/images/left/left_bu10.gif";

var bboff=new Image();
bboff.src="/images/left/left_bu00.gif";

var bcon=new Image();
bcon.src="/images/left/left_bu11.gif";

var bcoff=new Image();
bcoff.src="/images/left/left_bu01.gif";

var bdon=new Image();
bdon.src="/images/left/left_bu12.gif";

var bdoff=new Image();
bdoff.src="/images/left/left_bu02.gif";

var beon=new Image();
beon.src="/images/left/left_bu13.gif";

var beoff=new Image();
beoff.src="/images/left/left_bu03.gif";

var bfon=new Image();
bfon.src="/images/left/left_bu14.gif";

var bfoff=new Image();
bfoff.src="/images/left/left_bu04.gif";

var bgon=new Image();
bgon.src="/images/left/left_bu15.gif";

var bgoff=new Image();
bgoff.src="/images/left/left_bu05.gif";

var bhon=new Image();
bhon.src="/images/left/left_bu16.gif";

var bhoff=new Image();
bhoff.src="/images/left/left_bu06.gif";

var bion=new Image();
bion.src="/images/left/left_bu17.gif";

var bioff=new Image();
bioff.src="/images/left/left_bu07.gif";

var bjon=new Image();
bjon.src="/images/left/left_bu18.gif";

var bjoff=new Image();
bjoff.src="/images/left/left_bu08.gif";


function lefton(imgna){

   if(document.images)
   document[imgna].src=eval(imgna+'on.src');
   
      }

function leftoff(imgna){
   if(document.images)
   document[imgna].src=eval(imgna+'off.src');
      }