var limit = 8;

	var Roll = new Array();
		for(i=1;i<=limit;i++){
			Roll[i] = new Image(); Roll[i].src = "img/roll_on" + i + ".gif";
		}
	
	var Original = new Image();
	
	function RO(name,num){
		Original.src = document.images[name].src;
		document.images[name].src = Roll[num].src;
	}
	
	function reset(name){
		document.images[name].src = Original.src;
	}