Urania's Mirror
... that the mystery of who came up with the idea behind Urania's Mirror took over a hundred and seventy years to solve?
... that the mystery of who came up with the idea behind <i id="mwB9M"><b id="mwB9Q"><a href="./Urania's_Mirror" id="mwB9U" rel="mw:WikiLink" title="Urania's Mirror">Urania's Mirror</a></b></i> <i id="mwB9Y">(extract pictured)</i> took over a hundred and seventy years to solve?