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X-WR-CALDESC:1 February 1942: The German Navy introduced the 4-rotor Enigma
  enciphering machine device to their U-Boats. The German Navy's 4-rotor En
 igma gave U-boats a great advantage in the Atlantic\, since the Allies cou
 ld not read 4-rotor messages. U-boats ruled the seas again...until Joseph 
 Desch at the National Cash Register Company in Dayton\, Ohio\, designed th
 e U.S. Navy Cryptanalytic Bombe in 1943. \n\nLearn more about the Enigma e
 xhibit at the National Cryptologic Museum or read the NSA publication\, 'S
 olving the Enigma\,' by Jennifer Wilcox via the links at the bottom of thi
 s page. You can also read about the 4-rotor Enigma via the Cryptomuseum.or
 g site (a virtual museum) - see link below.\n\nExcerpted from NSA:\n\n'Pos
 sibly the most well known of all cipher machines is the German Enigma. It 
 became the workhorse of the German military services\, used to encrypt ten
 s of thousands of tactical messages throughout World War II. The number of
  mathematical permutations for every keystroke is astronomical. However\, 
 the Enigma is not famous for its outstanding security\, but rather for its
  insecurities. Allied forces were able to read most of the Enigma encrypte
 d messages throughout most of the war as a result of the tireless effort o
 f many Allied cryptologists.'\n\nExcerpted from the Cryptomuseum.com site:
  \n\n'In the U-boats\, the Enigma was usually located in the radio room\, 
 although in some cases it was carried out to the captain's quarters\, e.g.
  in case of a double encipherment (Sonderschlussel M). Most U-boats even h
 ad two Enigma machines available to cope with different keys around the sw
 itch-over point at midnight. One Enigma would then be left with the settin
 gs of the previous day\, whilst the other one was configured with the sett
 ings for the new day. As some messages were received with a delay\, they c
 ould quickly be tried with both keys. '\n\n
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BEGIN:VEVENT
UID:3bd0dc86-35c8-44d9-a6a2-37f96875d59d
DTSTAMP:20260424T093230Z
DESCRIPTION:1 February 1942: The German Navy introduced the 4-rotor Enigma 
 enciphering machine device to their U-Boats. The German Navy's 4-rotor Eni
 gma gave U-boats a great advantage in the Atlantic\, since the Allies coul
 d not read 4-rotor messages. U-boats ruled the seas again...until Joseph D
 esch at the National Cash Register Company in Dayton\, Ohio\, designed the
  U.S. Navy Cryptanalytic Bombe in 1943. \n\nLearn more about the Enigma ex
 hibit at the National Cryptologic Museum or read the NSA publication\, 'So
 lving the Enigma\,' by Jennifer Wilcox via the links at the bottom of this
  page. You can also read about the 4-rotor Enigma via the Cryptomuseum.org
  site (a virtual museum) - see link below.\n\nExcerpted from NSA:\n\n'Poss
 ibly the most well known of all cipher machines is the German Enigma. It b
 ecame the workhorse of the German military services\, used to encrypt tens
  of thousands of tactical messages throughout World War II. The number of 
 mathematical permutations for every keystroke is astronomical. However\, t
 he Enigma is not famous for its outstanding security\, but rather for its 
 insecurities. Allied forces were able to read most of the Enigma encrypted
  messages throughout most of the war as a result of the tireless effort of
  many Allied cryptologists.'\n\nExcerpted from the Cryptomuseum.com site: 
 \n\n'In the U-boats\, the Enigma was usually located in the radio room\, a
 lthough in some cases it was carried out to the captain's quarters\, e.g. 
 in case of a double encipherment (Sonderschlussel M). Most U-boats even ha
 d two Enigma machines available to cope with different keys around the swi
 tch-over point at midnight. One Enigma would then be left with the setting
 s of the previous day\, whilst the other one was configured with the setti
 ngs for the new day. As some messages were received with a delay\, they co
 uld quickly be tried with both keys. '\n\n
DTSTART;TZID=America/New_York:20260201T000000
DTEND;TZID=America/New_York:20260201T235900
LOCATION:
SUMMARY:1942: German Navy introduced 4-rotor Enigma
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