Iris L King (nee Brown)

I started work at BP on the 13th February 1942, aged 17, and was sent to Hut 7, later moving to the newly built Block C. I stayed there until the section was moved to Eastcote at the end of the war. Frederick Freeborn was Head of Section, assisted by Ronald and Norman Whelan – they had been seconded from the Hollerith Company at Welwyn Garden City. Jane Ford was the excellent Secretary and I was her clerical assistant during my time in Block C. It was always a very busy and noisy place with three-shift working.

In considering the significance of the work done there, I can confirm that although it has never been given much importance in the various books written about the Park, it certainly was an integral part of many code-breaking activities. Messages from all sections came in continuously, for the text to be transferred to punched cards and these to be sorted and collated and finally fan-fold listed for return. [I am not sure but think that one copy would be retained for our file and the punched cards eventually destroyed.] Further lists could be made from the original cards but sorted on different columns of the cards; this would save the decipherers a great deal of time. Mr Freeborn had regular meeting with Heads of Section and officers of the Services to plan the use of the machines.

One-time pads for the Royal Navy were compiled using cards punched with random letters, and code books for the RAF were printed each month. The number of staff is a calculated guess, possibly 300 or more, including civilians, Wrens and several airmen. Later some US Army officers joined the workforce.

Hollerith mechanics used one bay as a workshop for repairs and adaptations to the machines. The outstation at Drayton Parslow housed a small number of machines and had its own workshop adjacent to Mr. Freeborn’s house. This was also a very busy place with one or two punched tape machines probably used to transfer data from cards for storage. It had about 100 staff.

The general belief that Block C was a large filling cabinet is rather unfair and is not the whole story. Code-breaking was much speedier with its help and with the aid of the bombe machine housed in one of the south bays. I always think of the work done there as Stage 2 of the success of BP, to be followed in natural progression by Colossus as Stage 3.