"I should if I remembered my lines, I suppose."
"Very well," I said. "Then I should say, 'Friend.'"
"Well," said Arthur, "where's the catch?"
"There isn't a catch," I said. "What I want to know is, how do we go on after that?"
"I should ask you if you'd got such a thing as a cigarette about you," said Arthur.
"You might do that," I said, "but it doesn't sound helpful. The reason I ask is because I've read the instructions several times in the papers on the courtesies to be observed when meeting a sentry; but the scene always ends at this point—'Friend.' What happens next?"
"Perhaps the right thing," said Arthur, "would be for you to ask after the Colonel's wife. But I might not let you get as far as that. The odds would be in favour of my not believing you when you said 'Friend,' and in that case I should either shoot or pink you. The choice between these two processes would lie with me."
"But wouldn't that be rather sudden? Surely you make another remark first. I seem to remember something about 'sign and countersign.'"
"You're thinking of trigonometry, aren't you?" said Arthur.
"Perhaps I am," I said. "Anyway it's awkward not knowing what happens next."