At the November meeting Paul Rason addressed the Society on
"Knockholt's WW2 Secret".
From the beginning of the war British Intelligence had been
intercepting German messages in Morse code encrypted on Enigma
machines and eventually decoded at Bletchley Park.
Then new, non-Morse signals began to appear.
These were teleprinter messages, often of the first importance.
MI6 acquired Ivy Farm at Knockholt as a listening post to intercept
the new messages, transcribe the encrypted text, and send the
transcripts to Bletchley Park by dedicated telegram lines (that
is why the telephone exchange at Knockholt is so large) or by
despatch riders.
Encoded on the formidable Lorenz machines, these messages could
not be decoded until one German operator made some lazy mistakes,
and even then the work had to be done manually until Colossus
was built.
There were six workers at Ivy Farm in 1942, under the direction
of H. C. Kenworthy, seconded from Marconi; by 1945 there were
815, housed around the neighbourhood and brought to Knockholt
in shifts by special buses.
Ivy farmhouse is still there, in the centre of the village,
and can be glimpsed from Ivy Lane, but the 20-odd huts built
in the grounds have been taken down and replaced by a bowling
green.