// turn on img
	function turnOn(imgName) {
		if (document.images) {
			document[imgName].src = eval (imgName + '_' + '1.src');
		}
	}

	
	// turn off img
	function turnOff(imgName) {
		if (document.images) {
			document[imgName].src = eval (imgName + '_' + '0.src');
		}
	}