This cipher reel was captured by Union Forces at the surrender of Mobile, Alabama in May 1865. It is an extremely rare relic, being one of two known to have survived the American Civil War. It bears in feint pencilled notations, the names of the Confederate Signal Officer Captain Thomas Hawkings Clagett, Jr., of Leesburg VA and several of his men.

As a trophy of war, , it was sent to the Chief Signal Officer in Washington and later came into the hands of the Signals Intelligence Service, forerunner of the National Security Agency and the Army's Intelligence and Security Command. The reel used a centuries of cipher known today as the Vigenere. Poor security practices of Confederate users made a potentially sophisticated cipher vulnerable to being read.

 

An NCM exhibit. Click to enlarge. (Photos by Ralph Simpson)

Contributors and Credits:

1) Ralph Simpson <ralphenator(at)gmail.com>
2) NCM placard

Back To Menu Page

Apr 21/12