window.addEvent('domready', function() {
		var el1 = $('Layer1');
		$('toggleLayer1').addEvent('click', el1.fade.bind(el1, 'toggle'));
		var el2 = $('Layer2');
		$('toggleLayer2').addEvent('click', el2.fade.bind(el2, 'toggle'));
		var el3 = $('Layer3');
		$('toggleLayer3').addEvent('click', el3.fade.bind(el3, 'toggle'));
		var el4 = $('Layer4');
		$('toggleLayer4').addEvent('click', el4.fade.bind(el4, 'toggle'));
		var el5 = $('Layer5');
		$('toggleLayer5').addEvent('click', el5.fade.bind(el5, 'toggle'));
		var el6 = $('Layer6');
		$('toggleLayer6').addEvent('click', el6.fade.bind(el6, 'toggle'));
		var el7 = $('Layer7');
		$('toggleLayer7').addEvent('click', el7.fade.bind(el7, 'toggle'));
		var el8 = $('Layer8');
		$('toggleLayer8').addEvent('click', el8.fade.bind(el8, 'toggle'));
		var el9 = $('Layer9');
		$('toggleLayer9').addEvent('click', el9.fade.bind(el9, 'toggle'));
		var el10 = $('Layer10');
		$('toggleLayer10').addEvent('click', el10.fade.bind(el10, 'toggle'));
		var el11 = $('Layer11');
		$('toggleLayer11').addEvent('click', el11.fade.bind(el11, 'toggle'));
		var el12 = $('Layer12');
		$('toggleLayer12').addEvent('click', el12.fade.bind(el12, 'toggle'));
		var el13 = $('Layer13');
		$('toggleLayer13').addEvent('click', el13.fade.bind(el13, 'toggle'));
		var el14 = $('Layer14');
		$('toggleLayer14').addEvent('click', el14.fade.bind(el14, 'toggle'));
		var el15 = $('Layer15');
		$('toggleLayer15').addEvent('click', el15.fade.bind(el15, 'toggle'));
		var el16 = $('Layer16');
		$('toggleLayer16').addEvent('click', el16.fade.bind(el16, 'toggle'));
		var el17 = $('Layer17');
		$('toggleLayer17').addEvent('click', el17.fade.bind(el17, 'toggle'));
		var el18 = $('Layer18');
		$('toggleLayer18').addEvent('click', el18.fade.bind(el18, 'toggle'));
});

function hideAllSymbols(){
	for (var i=1; i<19; i++){
		document.getElementById('Layer'+i).fade("out");
		document.getElementById('toggleLayer'+i).checked=false;
	}}

function showAllSymbols(){
	for (var i=1; i<19; i++){
		document.getElementById('Layer'+i).fade("in");
		document.getElementById('toggleLayer'+i).checked=true;
	}}