function makeURL(user, domain, tld) 
    {
      if (domain == null) domain = "caves" ;
      if (tld == null)  tld = "org.uk" ;
      return ("mai" + "lto:" + user + "@" + domain + "." + tld) ;
    }

function localise(url)
    {
      if (location.protocol == 'file:')
      { 
        window.status = "URL converted to local version";
        return(url.replace(/http.*uk/,"../new_caves/public_html")) 
      }
      else
      { 
        return(url) 
      }
    }