var speed=50
   demo2.innerHTML=demo1.innerHTML 
   function Marquee(){
   if(demo2.offsetTop-demo.scrollTop<=0) 
   demo.scrollTop-=demo1.offsetHeight  
   else{
   demo.scrollTop++
   }
   }
   var MyMar=setInterval(Marquee,speed) 
   demo.onmouseover=function() {clearInterval(MyMar)}
   demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}