button1off = new Image(207,43);
button1on = new Image(207,43);
button1off.src="img/eoclevel-off.png";
button1on.src="img/eoclevel-on.png"; 

function imageOff1 (the_image) {

  document[the_image].src=eval(the_image + "off.src");
  }

function imageOn1 (the_image) {
  document[the_image].src=eval(the_image + 'on.src');
  }