<a href="https://en.wikipedia.org/wiki/Basil_Valentine" class="extiw" title="w:Basil Valentine">Basil Valentine</a>, The Third Key.  Illustration from  Basilius Valentinus, <i>The last vvill and testament of Basil Valentine, monke of the Order of St. Bennet : which being alone, he hid under a table of marble, behind the high-altar of the cathedral church, in the imperial city of Erford, leaving it there to be found by him, whom Gods providence should make worthy of it : to which is added two treatises, the first declaring his manual operations, the second shewing things natural and supernatural : never before published in English.</i> London : Printed by S. G. and B. G. for Edward Brewster ..., 1671, p. 239.
Basil Valentine in his writings provided twelve “keys,” a widely reproduced sequence of alchemical operations encoded allegorically, both in words and in images. The images were essential to the communication and had to depict the same scene, regardless of the artistry.
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Basil Valentine</div>
1671<div style="display: none;">date QS:P571,+1671-00-00T00:00:00Z/9</div>
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