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UID:342d8642-5bef-444d-afbd-1788be753dba
X-WR-CALDESC:12 August 1918: The 'Allegheny' field code was issued. Learn a
 bout American Army Field Codes in a document by William Friedman via the l
 ink at the bottom of the page.\n\nTrench codes were codes used for secrecy
  by field armies in World War I. A reasonably-designed code is generally m
 ore difficult to crack than a classical cipher\, but of course suffers fro
 m the difficulty of preparing\, distributing\, and protecting codebooks. T
 he Americans adopted a series of codes named after rivers\, beginning with
  'Potomac'. They learned to print the codebooks on paper that burned easil
 y and degraded quickly after a few weeks\, when the codes would presumably
  be obsolete\, while using a font that was easy to read under trench condi
 tions.
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DTSTART:20261101T020000
TZOFFSETFROM:-0400
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RDATE:20271107T020000
RDATE:20281105T020000
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DTSTART:20270314T020000
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RDATE:20280312T020000
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BEGIN:VEVENT
UID:39d55c7f-426e-4cbc-bee8-4de142634d5e
DTSTAMP:20260724T195305Z
DESCRIPTION:12 August 1918: The 'Allegheny' field code was issued. Learn ab
 out American Army Field Codes in a document by William Friedman via the li
 nk at the bottom of the page.\n\nTrench codes were codes used for secrecy 
 by field armies in World War I. A reasonably-designed code is generally mo
 re difficult to crack than a classical cipher\, but of course suffers from
  the difficulty of preparing\, distributing\, and protecting codebooks. Th
 e Americans adopted a series of codes named after rivers\, beginning with 
 'Potomac'. They learned to print the codebooks on paper that burned easily
  and degraded quickly after a few weeks\, when the codes would presumably 
 be obsolete\, while using a font that was easy to read under trench condit
 ions.
DTSTART;TZID=America/New_York:20270812T000000
DTEND;TZID=America/New_York:20270812T235900
LOCATION:
SUMMARY:1918: 'Allegheny' Field Code was issued.
END:VEVENT
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