Darkness at Noon by Arthur Koestler (1940)
Tap code in the mid-20th Century Russia.
“Darkness at Noon is a novel by Hungarian-born British novelist Arthur Koestler, first published in 1940. His best known work, it is the tale of Rubashov, an Old Bolshevik who is arrested, imprisoned, and tried for treason against the government that he helped to create”
They will shoot me, thought Rubashov. My motives will be of no interest to them. He leaned his forehead on the window pane. The yard lay white and still.
So he stood a while, without thinking, feeling the cool glass on his forehead. Gradually, he become conscious of a small but persistent ticking sound in his cell.
He turned round listening. The knocking was so quiet that at first he could not distinguish from which wall it came. While he was listening, it stopped. He started tapping himself, first on the wall over the bucker, in the direction of No. 406, but got no answer. He tried the other wall, which separated him from No. 402, next to his bed. Here he got an answer. Rubashov sat down comfortably on the bunk, from where he could keep on eye on the spy-hole, his heart beating. The first contact was always very exciting.
No. 402 was tapping regularly, three times with short intervals, then a pause, then again three times, then again a pause, then again three times. Rubashov repeated the same series to indicate that he heard. He was anxious to find out whether the other knew the ‘quadratic alphabet’ —otherwise three would be a lot of fumbling until he had taught it to him. The wall was thick, with poor resonance; he had to put his head close to it to hear clearly and at the same time he had to watch the spy-hole. No. 402 had obviously had a lot of practice; he tapped distinctly and unhurriedly, probably with some hard object such as a pencil. While Rubashov was memorizing the numbers, he tried, being out of practice, to visualize the square of letters with the 25 compartment —five horizontal rows with five letters in each. No. 402 first tapped five times —accordingly the fifth row: :V to Z; then twice; so it was the second letter of the row: W. Then a pause; then two taps —the second row, F-J; then three taps —the third letter of the row: H. Then three times and then five times; fifth letter of the third row: O. He stopped.
A practical person, thought Rubashov; he wants to know at once whom he has to deal with. According to the revolutionary etiquette, he should have started with a political tag; then given the news; then talked of food and tobacco; much latter only, days later, if at all, did one introduce oneself. However, Rubashov’s experience had been so far confined to countries in which the Party was persecuted, not persecutor, and the members of the Party, for conspiratorialreasons, knew each other only by their Christian names —and changed even these so often that a name lost all meaning. Here, evidently, it was different. Rubshov hesitated as to whether he should give his name. No. 402 became impatient; he knocked again: WHO?
Well, why not? thought Rubashov. He tapped out his full name: NICOLAS SALMANOVITCH RUBASHOV, and waited for the result