Describing the final part of Gradus’ sinister journey from Onhava (the beautiful capital of Kinbote's Zembla) to New Wye (a small University town in New England where Shade and Kinbote live), Kinbote (in VN's novel Pale Fire, 1962, Shade's mad commentator who imagines that he is Charles the Beloved, the last self-exiled king of Zembla) mentions a train dubbed the Square Wheel by jolted and jerked students:
Jacques d'Argus looked for a twentieth time at his watch. He strolled like a pigeon with his hands behind him. He had his mahogany shoes shined - and appreciated the way the dirty but pretty boy clacked taut his rag. In a restaurant on Broadway he consumed a large portion of pinkish pork with sauerkraut, a double helping of elastic French fries, and the half of an overripe melon. From my rented cloudlet I contemplate him with quiet surprise: here he is, this creature ready to commit a monstrous act - and coarsely enjoying a coarse meal! We must assume, I think, that the forward projection of what imagination he had, stopped at the act, on the brink of all its possible consequences; ghost consequences, comparable to the ghost toes of an amputee or to the fanning out of additional squares which a chess knight (that skip-space piece), standing on a marginal file, "feels" in phantom extensions beyond the board, but which have no effect whatever on his real moves, on the real play.
He strolled back and paid the equivalent of three thousand Zemblan crowns for his short but nice stay at Beverland Hotel. With the illusion of practical foresight he transferred his fiber suitcase and - after a moment of hesitation - his raincoat to the anonymous security, of a station locker - where, I suppose, they are still lying as snug as my gemmed scepter, ruby necklace, and diamond-studded crown in - no matter, where. On his fateful journey he took only the battered black briefcase we know: it contained a clean nylon shirt, a dirty pajama, a safety razor, a third petit-beurre, an empty cardbox box, a thick illustrated paper he had not quite finished with in the park, a glass eye he once made for his old mistress, and a dozen syndicalist brochures, each in several copies, printed with his own hands many years ago.
He had to check in at the airport at 2 P. M. The night before, when making his reservation, he had not been able to get a seat on the earlier flight to New Wye because of some convention there. He had fiddled with railway schedules, but these had evidently been arranged by a practical joker since the only available direct train (dubbed the Square Wheel by our jolted and jerked students) left at 5: 13 A. M., dawdled at flag stations, and took eleven hours to cover the four hundred miles to Exton; you could try to cheat it by going via Washington but then you had to wait there at least three hours, for a sleepy local. Buses were out so far as Gradus was concerned since he always got roadsick in them unless he drugged himself with Fahrmamine pills, and that might affect his aim. Come to think of it, he was not feeling too steady anyway. (note to Line 949)
A train dubbed the Square Wheel by students brings to mind Rudyard Kipling's story Brother Square-Toes (1910). The tale follows Pharaoh Lee, a Sussex smuggler nicknamed "Brother Square-Toes" for his broad-toed shoes, who travels to America in 1793 and meets Seneca leaders alongside President George Washington. It is also famous for first introducing Kipling's iconic poem If:
If you can keep your head when all about you
Are losing theirs and blaming it on you,
If you can trust yourself when all men doubt you,
But make allowance for their doubting too;
If you can wait and not be tired by waiting,
Or being lied about, don’t deal in lies,
Or being hated, don’t give way to hating,
And yet don’t look too good, nor talk too wise:
If you can dream—and not make dreams your master;
If you can think—and not make thoughts your aim;
If you can meet with Triumph and Disaster
And treat those two impostors just the same;
If you can bear to hear the truth you’ve spoken
Twisted by knaves to make a trap for fools,
Or watch the things you gave your life to, broken,
And stoop and build ’em up with worn-out tools:
If you can make one heap of all your winnings
And risk it on one turn of pitch-and-toss,
And lose, and start again at your beginnings
And never breathe a word about your loss;
If you can force your heart and nerve and sinew
To serve your turn long after they are gone,
And so hold on when there is nothing in you
Except the Will which says to them: ‘Hold on!’
If you can talk with crowds and keep your virtue,
Or walk with Kings—nor lose the common touch,
If neither foes nor loving friends can hurt you,
If all men count with you, but none too much;
If you can fill the unforgiving minute
With sixty seconds’ worth of distance run,
Yours is the Earth and everything that’s in it,
And—which is more—you’ll be a Man, my son!
In the same note of his commentary Kinbote calls Gradus (Shade's murderer) a "half-man who is also half mad:"
I have considered in my earlier note (I now see it is the note to line 171) the particular dislikes, and hence the motives, of our "automatic man," as I phrased it at a time when he did not have as much body, did not offend the senses as violently as now; was, in a word, further removed from our sunny, green, grass-fragrant Arcady. But Our Lord has fashioned man so marvelously that no amount of motive hunting and rational inquiry can ever really explain how and why anybody is capable of destroying a fellow creature (this argument necessitates, I know, a temporary granting to Gradus of the status of man), unless he is defending the life of his son, or his own, or the achievement of a lifetime; so that in final judgment of the Gradus versus the Crown case I would submit that if his human incompleteness be deemed insufficient to explain his idiotic journey across the Atlantic just to empty the magazine of his gun; we may concede, doctor, that our half-man was also half mad. (note to Line 949)
Doctor mentioned by Kinbote suggests that Botkin (Shade's, Kinbote's and Gradus' "real" name) writes his commentary, index and foreword (in that order) to Shade's poem not in "Cedarn, Utana," but in a madhouse near Quebec - in the same sanatorium where Humbert Humbert (the narrator and main character in VN's novel Lolita, 1955) writes his poem "Wanted" after Lolita's escape from (or, more likely, death in) the Elphinstone hospital on July 4, 1949 (the American Independence Day).