This isn't really a spoiler as the chapter title alludes to the chase which comprises the major element of the chapter.

In this chapter Sunday is pursued through London while he uses various and increasingly bizarre forms of transportation all the while hurling notes at his pursuers.

This chapter was a major turnoff when I first read it as it is so farcical that I felt I was being made a fool of. However, once you grasp Chesterton's point, the entire thing makes perfect sense and is genius.

Here are the notes that Sunday drops during the chase through London, first in a cab, then on a fire engine, then on an elephant taken from the London Zoo, and finally in a hot air balloon.

To Bull - “What about Martin Tupper now?”

To Syme - “No one would regret anything in the nature of an interference by the Archdeacon more than I. I trust it will not come to that. But, for the last time, where are your galoshes? The thing is too bad, especially after what uncle said.”

To Ratcliffe - “‘Fly at once. The truth about your trouser-stretchers is known.’ - A Friend.”

To Gogol - “The word, I fancy, should be ‘pink.’”

To the Secretary - “‘When the herring runs a mile, / Let the Secretary smile; / When the herring tries to fly, / Let the Secretary die.’ Rustic Proverb.”

To the Professor - “‘Your beauty has not left me indifferent.’ - From Little Snowdrop.”

I have continued to poke about the silly notes Sunday tossed at the detectives.

Two of the notes contain an italicized word.

I edited the initial post in this discussion to show those words.

"To Bull - “What about Martin Tupper now?”
"When the herring tries to fly,"

It isn't much, but if you take the two italicized words together they form a short sentence;

"Now fly."

I point out that immediately after Sunday commandeers the Captive Balloon and flies away with the detectives in pursuit.

Also notice that the note containing the word 'fly' is in a four line poem which feels to me like a Clerihew a poetic form which Edmund Clerihew Bentley, the subject of the dedication of TMWWT, invented.

Clerihews are precisely structured poems consisting of 4 lines with a rhyming pattern of AABB.

A “When the herring runs a mile,
A Let the Secretary smile;
B When the herring tries to fly,
B Let the Secretary die.’
Rustic Proverb.”

A 'Rustic Proverb' might also be Chesterton's slang for a Clerihew.

Clerihews usually were biographical. The 'herring' note was dropped to the Secretary, the only detective who is unmasked but not named. I wonder if "The Herring," is intended to be someone of Chesterton's era.

Thanks for the interesting analysis of the 'notes', or perhaps they could be referred to as 'clues'? I really like this one ... “‘Your beauty has not left me indifferent.’ - From Little Snowdrop.”

Reflecting on Chesterton's dream or nightmare theme, I think the pursuit sequences, including pursuit of the President but also the earlier pursuit of Syme, and also the changing of identities and the resulting confusion are quite typical elements of dreams or nightmares. I think Chesterton does an excellent job of creating a nightmare full of fear, confusion and suspense, which results in that head spinning feeling associated with nightmares ..

This made me think of Alice Cooper's famous line 'welcome to my nightmare, welcome to my breakdown' .. so just for a little entertainment I looked up 'Welcome to my Nightmare' on Youtube and found this rather awful video .. bit of nightmare in itself ... quite the low end production, or perhaps its as old as the song itself and was shot with a Super 8 camera.

http://www.youtube.com/watch?v=iQE0pfBAYQ8