A paper by <a href="https://en.wikipedia.org/wiki/David_Brewster" id="mwVg" rel="mw:WikiLink" title="David Brewster">David Brewster</a> is read to the <a href="https://en.wikipedia.org/wiki/Royal_Society" id="mwVw" rel="mw:WikiLink" title="Royal Society">Royal Society</a>, belatedly announcing his discovery of what we now call the <i id="mwWA">biaxial</i> class of <a href="https://en.wikipedia.org/wiki/Birefringence" id="mwWQ" rel="mw:WikiLink" title="Birefringence">doubly-refracting</a> crystals.<sup about="#mwt59" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-9"}}' id="cite_ref-9" rel="dc:references" typeof="mw:Extension/ref"><a href="./January_15#cite_note-9" id="mwWg" style="counter-reset: mw-Ref 9;"><span class="mw-reflink-text" id="mwWw">[9]</span></a></sup> On the same day, <a href="https://en.wikipedia.org/wiki/Augustin-Jean_Fresnel" id="mwXA" rel="mw:WikiLink" title="Augustin-Jean Fresnel">Augustin-Jean Fresnel</a> signs a "supplement" (submitted four days later) on reflection of <a href="https://en.wikipedia.org/wiki/Polarization_(waves)" id="mwXQ" rel="mw:WikiLink" title="Polarization (waves)">polarized</a> light.
<span class="mw-reference-text" id="mw-reference-text-cite_note-9"><cite about="#mwt56" class="citation book cs1" id="CITEREFRoyal_Society_(Great_Britain)1833">Royal Society (Great Britain) (1833). <a class="external text" href="https://books.google.com/books?id=bVdCAQAAMAAJ&amp;pg=PA92" id="mwCAY" rel="mw:ExtLink nofollow"><i id="mwCAc">Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London</i></a>. Richard Taylor. pp.<span id="mwCAg" typeof="mw:Entity"> </span>92–.</cite><span about="#mwt56" class="Z3988" id="mwCAk" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Abstracts+of+the+Papers+Printed+in+the+Philosophical+Transactions+of+the+Royal+Society+of+London&amp;rft.pages=92-&amp;rft.pub=Richard+Taylor&amp;rft.date=1833&amp;rft.au=Royal+Society+%28Great+Britain%29&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DbVdCAQAAMAAJ%26pg%3DPA92&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AJanuary+15"></span></span>