SImPSON | 417
worth pursuing. Finding these was beyond the reach of manual methods, and the search was
performed, starting afresh each day, by the Freebornery, the Hollerith section under Frederic
Freeborn, which was first located in Hut 7 and later occupied all of Block C.
As Ronald Whelan, Freeborn’s deputy, has written:^2
The daily Hollerith processing carried on in Hut 7/Block C in dealing with the Enigma message
texts was accorded the highest priority. The requirement was to search through the day’s traffic
to locate [tetragram] repeats occurring between messages. The teleprinter material was edited
in Hut 8 . . . These edited message texts were then made available to Hut 7/Block C without
delay throughout the day.
Although dealing with small batches of cards, in this way, was wasteful of machine operator
time, as well as affecting machine availability for less important work, it did enable the output
results to be made available to Hut 8 in the shortest possible time following their advice that the
‘cut’ was to be made: that the final batch of messages had been made available to us . . .
It was the case that the daily Enigma traffic gave rise to a total of around 80,000 cypher text
characters. The Hollerith processing in dealing with this material called for slick and expert
machine operation, and involved a large number of machines for many of the operations . . .
The ‘cut’ instruction from Hut 8 was liable to be made late in the evening, in which case the
Team Leader would draft many machines and operators to the work to gain the earliest pos-
sible completion. This did not necessarily mean that an operator was needed for each machine
pressed into service, because many operators were adept in running two or more machines at
the same time.
Sybil Griffin joined Bletchley Park early in 1940 as a Foreign Office civilian, at the age of 17.
Recalling Tetras as a routine daily job in the Hollerith section, and illustrating the variety of
Hollerith machines in use, she recalls:^3
On Tetras we were in teams of civilians—the Wrens came later. The Team Leader was in charge
but we all got on with the job in hand.
Basically we were looking for 4-letter repeats. The messages were punched on to cards in sec-
tions of 26 letters and cards were taken to the machine room. A duplicate card was made using the
Reproducer, which was in another room, and one card was stored. (Some people thought that was
all we did!) Then 25 blank cards were inserted behind each master card using a Collator. All cards
then went back to the Reproducer, where 4 letters at a time were rotated. The cards were then
sorted: there was a row of Sorters working together, maybe six. Lists were printed, in yet another
room, and sent to sections needing them to look for repeats and patterns to break in to Enigma.
We could chat and spoke of social activities, dances, trips to London, etc. We used to go up
to London by train after the midnight to 9 am shift. It was possible, if rather exhausting, for one
person to run several machines. I remember being on duty one weekend (after a week training
Wrens) and working alongside an American serviceman. We ran all the Sorters, Collators and
Listers between us because there was nobody else on duty!
Ronnie Whelan kept in constant touch during a day’s work and Mr Freeborn walked round
often, always bringing visitors to Hut 7/Block C. When VIPs visited Bletchley Park they always
visited us. I remember Admiral Cunningham, Sir Charles Portal, and Lord Louis Mountbatten
being shown around. Churchill visited BP.^4 The Scharnhorst was sunk on Boxing Day 1943 and
Admiral Sir Bruce Fraser gave a lecture to tell all of us involved how much we had helped when
Scharnhorst and Bismarck were sunk, and we in Block C were invited.