Tuesday, May 20, 2014

Ciphers

Image via Le Wik
Encryption has been used for a long, long time - one of the oldest known methods is called the Caesar Cipher, after Julius himself.  While there have been many methods used through the ages all involve rearranging the data to hide the message.  One of the cleverest was done my the early Irish republican Arthur O'Connor.

O'Connor was a big fan of the recent American Revolution and was absolutely mad for the French Revolution, in full bruit across the Channel.  He even went so far as to petition the French Revolutionary government for aid in throwing off the English yoke.

Naturally, this sort of activity made him well known to the local constabulary, and he was arrested and tried.  As he was about to be sentenced, he announced a stunning repudiation of his formal radical philosophy, and produced a poem that he had written as evidence for his change of heart.

The poem is reproduced in full here:
The pomp of courts, and pride of kings,
I prize above all earthly things;
I love my country, but my king,
Above all men his praise I'll sing.
The royal banners are display'd,
And may success the standard aid:

I fain would banish far from hence
The Rights of Man and Common Sense.
Destruction to that odious name,
The plague of princes, Thomas Paine,
Defeat and ruin seize the cause
Of France, her liberty, and laws.
As you can imagine, this pleased the judge no end, and seeing the usefulness of the conversion of a man of O'Connor's stature, he was released from prison and walked out of the court a free man.

But he'd foxed them.  The poem was enciphered.  The "decryption" algorithm was to read a line from the first verse, followed by a line from the second.  Then the next in the first verse, and the next in the second.  You can do that yourself, but it comes out like this:
The pomp of courts, and pride of kings,
I fain would banish far from hence
I prize above all earthly things;
The Rights of Man and Common Sense.
I love my country, but my king,
Destruction to that odious name,
Above all men his praise I'll sing.
The plague of princes, Thomas Paine,
The royal banners are display'd,
Defeat and ruin seize the cause
And may success the standard aid:
Of France, her liberty, and laws.
It was right in front of their eyes, but hidden from view.  O'Connor caught passage to France where be ended up a general in Napoleon's army and lived to the ripe age of 89.  Not the strongest cipher ever invented, but adequate to fool the Upper Class Twit of the Year for 1804.

1 comment:

Old NFO said...

That is well done, and 'easy' once one know which way to read it... ;-)