There are no typos. The text is mirrored/flipped. I wasn't aware I could do that here. As another replied, reading the poem is a requirement for truly understanding both the snark and boojum metaphors
The text here is an altered version of:
"She had softly and suddenly vanished away,
For the Snark was a Boojum, you see."
A quote from the poem "The Hunting of the Snark" by Lewis Carrol