Cryptographic History of Work on the German Naval Enigma


Americans priority letters were attached and the jobs got run in corresponding order on the American machines. This arrangement, which worked extremely smoothly, is an excellent example of the advantages of an inter-service organization for work of this kind, had our Naval Section been entirely separate from its opposite numbers on the Air and Army side so that only Naval jobs got run on the Op. 20 G bombes an enormous amount (well over half) the total bombe time would have been frittered away through inability on our part to keep the machines fully occupied.

12. Hut 6 jobs were always known as "Bovril" and were of 3 grades D, E and F - I am quite unable to remember exactly how this peculiar nomenclature arose: A typical priority list is the following covering the first week of August 1944

1. Shark

2. Bonito, Dolphin, D Bovril

3. Porpoise

4. E Bovril

5. Plaice

6. Grampus

7. Turtle, F Bovril.

13. The only other notable event in September was a "split" in Porpoise, the Black Sea going on to a key of its own, Grampus. The new key also threw-on and therefore gave little trouble; it was a welcome addition to the work as far as the non-cribsters were concerned.


October.

14. The most interesting event in October was the breaking of Shark on the "Biscay Weather" crib on October 24th. Previously almost all our Shark breaks (except those on Short Signals) had been on R.E's from Dolphin; the "B. W.", which was the only regular weather message, was so unpredictable in its phraseology as to be useless except for getting out "paired days" on which one could afford to make a large number

-64-


< previous

next >