function toggleLayer( whichLayer )
		{
		  var elem, vis;
		  if( document.getElementById ) // this is the way the standards work
			elem = document.getElementById( whichLayer );
		  else if( document.all ) // this is the way old msie versions work
			  elem = document.all[whichLayer];
		  else if( document.layers ) // this is the way nn4 works
			elem = document.layers[whichLayer];
		  vis = elem.style;
		  // if the style.display value is blank we try to figure it out here
		  if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined)
			vis.display = (elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none';
		  vis.display = (vis.display==''||vis.display=='block')?'none':'block';
		};

function showLayer( whichLayer )
		{
		  var elem, vis;
		  if( document.getElementById ) // this is the way the standards work
			elem = document.getElementById( whichLayer );
		  else if( document.all ) // this is the way old msie versions work
			  elem = document.all[whichLayer];
		  else if( document.layers ) // this is the way nn4 works
			elem = document.layers[whichLayer];
		  vis = elem.style;
		  // if the style.display value is blank we try to figure it out here
		  if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined)
			vis.display = (elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none';
		  vis.display = (vis.display=='')?'none':'block';
		};
		
function hideLayer( whichLayer )
		{
		  var elem, vis;
		  if( document.getElementById ) // this is the way the standards work
			elem = document.getElementById( whichLayer );
		  else if( document.all ) // this is the way old msie versions work
			  elem = document.all[whichLayer];
		  else if( document.layers ) // this is the way nn4 works
			elem = document.layers[whichLayer];
		  vis = elem.style;
		  // if the style.display value is blank we try to figure it out here
		  if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined)
			vis.display = (elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none';
		  vis.display = (vis.display=='')?'block':'none';
		};