lighter than air
...that there are 14 gases which are lighter than air?
...that there are 14 <a href="./Gas" id="mwAdI" rel="mw:WikiLink" title="Gas">gases</a> which are <b id="mwAdM"><a class="mw-redirect" href="./Lighter_than_air" id="mwAdQ" rel="mw:WikiLink" title="Lighter than air">lighter than air</a></b>?