The Hunting of the Snark is a nonsense poem written by English writer Lewis Carroll between 1874 and 1876. The plot follows a crew of ten trying to hunt the Snark, which may turn out to be a highly dangerous Boojum. This original illustration by Henry Holiday accompanies the verse:
"But oh, beamish nephew, beware of the day,
If your Snark be a Boojum! For then
You will softly and suddenly vanish away,
And never be met with again!"