Snark and Boojum

John Tufail’s The Illuminated Snark lead me to this comparison. He interpreted the starry night sky in the Snark front cover illustration as a map. And I already found out, that Holiday alluded to artwork by Marcus Gheeraerts (the younger and the elder). So I searched for a Gheeraerts painting with a map. That guided me to the Ditchley Portrait.

 

 
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