Great Gulf
... that European cartographers initially considered the Pacific Ocean to be Ptolemy's Great Gulf?
... that European cartographers initially considered the <a href="./Pacific_Ocean" id="mw5w" rel="mw:WikiLink" title="Pacific Ocean">Pacific Ocean</a> to be <a href="./Ptolemy" id="mw6A" rel="mw:WikiLink" title="Ptolemy">Ptolemy</a>'s <b id="mw6Q"><a href="./Magnus_Sinus" id="mw6g" rel="mw:WikiLink" title="Magnus Sinus">Great Gulf</a></b>?