if (document.images) {

say1on = new Image();
say1on.src = "img/sgoku_on.jpg";

say1off = new Image();
say1off.src = "img/sgoku_off.jpg";

say2on = new Image();
say2on.src = "img/ssanzo_on.jpg";

say2off = new Image();
say2off.src = "img/ssanzo_off.jpg";

say3on = new Image();
say3on.src = "img/sgojyo_on.jpg";

say3off = new Image();
say3off.src = "img/sgojyo_off.jpg";

say4on = new Image();
say4on.src = "img/shakkai_on.jpg";

say4off = new Image();
say4off.src = "img/shakkai_off.jpg";

}

function sayon(jdd){
if (document.images){
document[jdd].src = eval(jdd + "on.src");
			}
		}
		
function sayoff(jdd){
if (document.images){
document[jdd].src = eval(jdd + "off.src");
		  }
		}