function show_map()
{
	var width = 256;
	var height = 725;
	var left = Math.floor((screen.width - width) / 2);
    var top = Math.floor((screen.height - height) / 2);
	
	var target = 'show_map.php';
	
	
	window.open(target, "zoom_window", "toolbar=no, location=0, directories=0, status=no, menubar=0, scrollbars=1, resizable=no, copyhistory=0, left="+left+", top="+top+", width="+width+", height="+height+", alwaysRaised=yes");

}