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METHOD:PUBLISH
UID:947ac8ee-76bb-4cc6-8927-4290b77dcb32
X-WR-CALDESC:2 September 1918: The 'Hudson' 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.
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DTSTART:20251102T020000
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
RDATE:20261101T020000
RDATE:20271107T020000
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DTSTART:20260308T020000
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TZOFFSETTO:-0400
RDATE:20270314T020000
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BEGIN:VEVENT
UID:784700ef-1e1a-4b3c-8f2a-598b08e49daf
DTSTAMP:20260424T125000Z
DESCRIPTION:2 September 1918: The 'Hudson' field code was issued. Learn abo
 ut American Army Field Codes in a document by William Friedman via the lin
 k at the bottom of the page.\n\nTrench codes were codes used for secrecy b
 y field armies in World War I. A reasonably-designed code is generally mor
 e difficult to crack than a classical cipher\, but of course suffers from 
 the difficulty of preparing\, distributing\, and protecting codebooks. The
  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 b
 e obsolete\, while using a font that was easy to read under trench conditi
 ons.
DTSTART;TZID=America/New_York:20260902T000000
DTEND;TZID=America/New_York:20260902T235900
LOCATION:
SUMMARY:1918: Hudson Field Code
END:VEVENT
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