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METHOD:PUBLISH
UID:7620eab9-fe59-4b87-8d09-751a4c4b3034
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:20281105T020000
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
RDATE:20291104T020000
RDATE:20301103T020000
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DTSTART:20290311T020000
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TZOFFSETTO:-0400
RDATE:20300310T020000
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BEGIN:VEVENT
UID:9fe32163-33cd-49ea-8602-4de3ccd55a24
DTSTAMP:20260426T203213Z
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:20290902T000000
DTEND;TZID=America/New_York:20290902T235900
LOCATION:
SUMMARY:1918: Hudson Field Code
END:VEVENT
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