Re: Another history question was Re: Tunny and SIGABA

From: Don Chiasson (don_chiasson_at_notmail.com)
Date: 06/09/03 

Date: Mon, 09 Jun 2003 16:00:37 GMT

"John A. Malley" <102667.2235@compuserve.com> wrote in message
news:3EE41A6F.4050107@compuserve.com...
> Michael Amling wrote:
>
> > Don Chiasson wrote:
> >
> >>
> >> A story I read said that at one stage a new wheel had just been
> >> introduced and the codebreakers were stymied. The suspicion
> >> was that early messages were test messages and one of the
> >> codebreakers noticed that the letter X (or some other, it matters
> >> not) did not occur. She hypothesized that the message sender
> >> was simply repeatedly pressing the X key. This proved enough
> >> to solve the new wheel. (Can't remember where I read this, it
> >> may have been "Enigma: the battle for the code" by
> >> Sebag-Montefore or perhaps "Battle of Wits" by Budiansky.)
> >
> >
> > It's not in Battle of Wits.
> >
> > --Mike Amling
> >
>
> It's in "Decrypted Secrets, Methods and Maxims of Cryptology" by
> F.L.Bauer, (ISBN ), Chapter 22 "Concluding Remarks", section
> 22.2.3 on page 413 in the first edition:
>
> "[snip] ........and the formally gifted
> Germanic philologist Mavis Batey nee Lever. Her abilities can be
> illustrated by the fact that she noticed one day the absence of
> the letter L in a long fragment of ENIGMA ciphertext.
> To notice this was already unheard of. But she also concluded
> that there was a long filling with plaintext /l/. This lead to the
> determination of the setting, to a break, and to the victory of the
> British fleet over the Italian on March 28, 1941, near Cape Matapan
> on the Greek coast."
[snip...]

Mavis Lever, that's the name! I checked, and the item I recall is in
Sebag-Montefiore, page 103. She is mentioned several other times
in the book. Thanks.

---Don
e-mail: it's not not, it's hot.