var spot=0;
var timer, timer2;
function scrollup(){
		if (spot>=20){
		spot=spot-30;
		document.getElementById('body_text').scrollTop=spot;;
			}
		}
	
function scrolldown(){
		if (spot<=3000){
		spot=spot+30;
		document.getElementById('body_text').scrollTop=spot;
		}
	}

function startscrollup(){
	timer=setInterval("scrollup()", 80);
	}
	
function startscrolldown(){
	timer2=setInterval("scrolldown()", 80);
	}