function GetHeightsCW (cat, wth)  
{
	block = "heights";
	$(block).innerHTML = '<img src="/images/loading.gif">';
	url = "call_heightscw.php?cat=" + cat + "&wth=" + wth;
	new Ajax.Updater(block, url, {onComplete:function(){ new Effect.Appear(block);}, asynchronous:true});
}