Breakfast at five-o’clock tea

Snark mark 2/5:

Its habit of getting up late you’ll agree
 That it carries too far, when I say
That it frequently breakfasts at five-o’clock tea,
 And dines on the following day.

There neither were internationally defined time zones nor an internationally agreed date line when Charles Darwin and the HMS Beagle travelled around the world, but when he breakfasted in Tahiti, it probably already was around tea time back home in the United Kingdom.

Exerpt from The Voyage of the Beagle, Chapter 18, Tahiti

Crossing the Line

  • [left]: Illustration The Crew on Board by Henry Holiday to Lewis Carroll’s The Hunting of the Snark (1876)
  • [right]: Crossing the Line (1839), based on a print by Thomas Landseer, after Augustus Earle. You will find the print in Robert Fitz-Roy’s Narrative of the surveying voyages of HMS Adventure and Beagle, Vol II (1839).

This is of of the comparisons where am not so sure whether Holiday alluded to Landseer’s print. If it is, then you might wait a little bit before you look at my spoiler where I marked possible(?) clues given to us by Holiday.
 

2017-11-08, updated: 2019-06-16

Delightful Monster


Monsters, by Henry Holiday (left) and J. J. Grandville (right).
 

[…] One of the first three [illustrations] I had to do was the disappearance of the Baker, and I not unnaturally invented a Boojum. Mr. Dodgson wrote that it was a delightful monster, but that it was inadmissible. All his descriptions of the Boojum were quite unimaginable, and he wanted the creature to remain so. I assented, of course, though reluctant to dismiss what I am still confident is an accurate representation. I hope that some future Darwin in a new Beagle will find the beast, or its remains; if he does, I know he will confirm my drawing. […]

(Henry Holiday (1898): The Snark’s Significance)

 
Once you meet the Boojum, you might be Going Slightly Mad.