function MoveLeft(){
	   var current_slide = parseInt($('current_slide').value) - 1;
	   var left = parseInt($('roller').getStyle('marginLeft'))+858;
	   if(current_slide < 1){
		current_slide = $('num_slides').value;
		left = -((parseInt($('num_slides').value)-1)*parseInt($('ScrollBox').getStyle('width')));
		}
		if(left==0||left==-858){
		Move(current_slide, left);
		}
		}
	
	
	function MoveRight(){
		var current_slide = parseInt($('current_slide').value) + 1;
		var left = parseInt($('roller').getStyle('marginLeft'))-858;
		if(current_slide > 3){
			current_slide = $('num_slides').value;
			left = -((parseInt($('num_slides').value)-1)*parseInt($('ScrollBox').getStyle('width')));
		}
		if(left==-858||left==-1716){
		Move(current_slide, left);
		}
		}
	
	function Move(current_slide, left){
		var bigBox = $('roller');
		new Fx.Style(bigBox, 'marginLeft', {
		transition: Fx.Transitions.Sine.easeInOut
		}).start(left);
		$('current_slide').value = current_slide;
		}