GCHQ - Eastcote 21° 02′N, 105°51′E
30th May 1949.
Dear Mr Michael Cum,
We have just
intercepted a message from our French ally.
Can you try to dechiper it?
We are lucky: the
French hired a new telegraphist: Firmin.
He resets the key at the end of each sentence.
Hug Alexander, H
section chief,
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8N
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RESRL99