td.time {
		display: none;
		width:30%;
		height:auto;
        }

<script type="text/javascript" src="prototype.js"></script>
<script language="JavaScript" type="text/javascript">
function toggleLayer()
{
if (document.getElementById)
{

tables = document.getElementsByTagName('td')

	for (var i=0; i < tables; i++) {
	{
	
		if (Element.hasClassName(tables[i], 'time')) {

		
var style2 = time[i].style;
style2.display = style2.display? "":"block";
}
	}
}
}
}

</script>

<td class="time">