I believe I do have a timeline of events that you might find educational.
He explains that Aristotle was wrong to claim that heavy things fall faster than lighter things. He uses a short poem to remind them of this:
Whether they’re large or whether they’re small,
Has no effect on the rate which things fall.
But whether you choose to accept this or not-le,
Depends on your faith in that fool, Aristotle.
He asks one of his students, Spencer, who it was that proved Aristotle wrong in 1592. Spencer, who had not been listening, incorrectly guesses Plato. The answer was Galileo.
Spencer explains that the SOE communicates with field agents using “poem codes”. The message sender and recipient encrypt their messages based on an agreed upon passage of text. For security, this text must be carried in the agent’s head, but not be something well known generally.
The passages need to be intensely memorable, unpredictable and, ideally, consist of twenty-six words.
Spencer recalled the rhymes that Newt used to teach him in class as memory aids, and thought that Newt could help with this. He tells him that suitable passages were in great demand.