Double Bluff!

    There is a scene in Hammer Into Anvil in which No.6 writes out a message to XO4, signed D6, on his writing pad in his cottage. He then tears off the next sheet of paper, because of the indentation left by his writing, so that no-one could detect the message through the indentations on that sheet of paper. Both of which he carefully folds and puts in his blazer pocket.
   But this is a double bluff on the part of No.6. Because No.2 is still able to detect the written message to XO4 from D6 from the third sheet of paper retrieved by No.14 from the note pad in No.6's cottage. No.2 does this through technology called Electrostatic Detection. He might have gained the message by the use of a lead pencil, by smearing the lead over the paper, but only if the indentations of No.6's writing were still deep enough on that third sheet of paper to be detected.
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