function extractImageTitles()
	{
	images = document.getElementsByTagName('img');
	for (var i = 0; i < images.length; i++)
		{
		var title = images[i].getAttribute('title');
		if ((title) && (title != ''))
			{
			if (title.match('http://', 'i'))
				{
				newlink = document.createElement('a');
				newlink.setAttribute('href', title);
				newlink.setAttribute('title', ('Go to ' + title));
				newlink.appendChild(document.createTextNode('Image source'));
				var newdiv = document.createElement('div');
				newdiv.className = 'caption';
				newdiv.appendChild(newlink);
				images[i].parentNode.appendChild(newdiv);
				images[i].removeAttribute('title');
				}
			else
				{
				var newdiv = document.createElement('div');
				newdiv.className = 'caption';
				newdiv.appendChild(document.createTextNode(title));
				images[i].parentNode.appendChild(newdiv);
				images[i].removeAttribute('title');
				}
			}
		}
	}

function createCookie(name,value,days)
{
	if (days)
	{
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	if (!readCookie(name)) {
		document.cookie = name+"="+value+expires+"; path=/";
	}
}

function createnewCookie(name,value,days)
{
	if (days)
	{
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name)
{
	var nameEQ = name + "=";
	var ca = document.cookie.split(';');
	for(var i=0;i < ca.length;i++)
	{
		var c = ca[i];
		while (c.charAt(0)==' ') c = c.substring(1,c.length);
		if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
	}
	return null;
}

function eraseCookie(name)
{
	createCookie(name,"",-1);
}

rnd.today=new Date();
rnd.seed=rnd.today.getTime();

function rnd() {
    rnd.seed = (rnd.seed*9301+49297) % 233280;
    return rnd.seed/(233280.0);
};

function rand(number) {
    return Math.ceil(rnd()*number);
};

var refer=document.referrer;
createnewCookie('referer',refer,0);
doc=document.location;
createnewCookie('document',doc,0);
tid = new Date();
timeid = tid.getTime();
if (!readCookie('sessionid')) {
   createCookie('sessionid',timeid,0);
}
if (readCookie('userid')) {
   var myuserid = readCookie('userid');
   if (myuserid.length < 14) {
      eraseCookie('userid');
   }
}
if (readCookie('__utmv')) {
   var myutmv = readCookie('__utmv');
   if (myutmv.length < 24) {
      eraseCookie('__utmv');
   }
}
if (!readCookie('__utmv') && readCookie('userid')) {
var myuserid = readCookie('userid');
document.cookie = "__utmv=30225952."+myuserid+"; expires=Sun, 18 Jan 2038 00:00:00 GMT; path=/; domain=.ndg.nerc.ac.uk;";
}