Steganography is the art and science of writing hidden messages in such a way that no one apart from the sender and intended recipient even realizes there is a hidden message. By contrast, cryptography obscures the meaning of a message, but it does not conceal the fact that there is a message. For shorthand see stenography.
Johannes Trithemius was an Abbot who wrote Steganographia in 1499. It was placed on the Index Librorum Prohibitorum in 1609. This book is in three volumes, and appears to be about black magic - specifically, about using spirits to communicate over long distances. Since the publication of the decryption key to the first two volumes in 1606, they have been known to be actually concerned with cryptography and steganography. Until recently, the third volume was widely still believed to be about magic - but recently the "magical" formulae were shown to be covertexts for yet more cryptography content.
Friday, July 18, 2008
Invisible Ink
Inks developed by heat
Some of these are organic substances that oxidize when heated, which usually turns them brown. For this type of 'heat fixed' ink, any acidic fluid will work. As a rule of thumb, the most secure way to use any particular ink is by diluting it - usually with water - near to the point when it begins to get difficult to develop.
* Cola drink (diluted)
* Honey (diluted)
* Lemon, apple or orange juice
* Milk
* Onion juice
* Semen - Sir George Mansfield Smith-Cumming, head of the British Secret Intelligence Service noted of his agents that "Every man carries his own stylo".
* Soap water
* Sugar solution
* Urine
* Vinegar or wine
* Cobalt chloride turns blue when heated and becomes invisible again after a while (if not overly heated)
The writing is made visible by heating the paper, either on a radiator, by ironing it, or by placing it in an oven. A 100 W light bulb is less likely to damage the paper.
Some of these are organic substances that oxidize when heated, which usually turns them brown. For this type of 'heat fixed' ink, any acidic fluid will work. As a rule of thumb, the most secure way to use any particular ink is by diluting it - usually with water - near to the point when it begins to get difficult to develop.
* Cola drink (diluted)
* Honey (diluted)
* Lemon, apple or orange juice
* Milk
* Onion juice
* Semen - Sir George Mansfield Smith-Cumming, head of the British Secret Intelligence Service noted of his agents that "Every man carries his own stylo".
* Soap water
* Sugar solution
* Urine
* Vinegar or wine
* Cobalt chloride turns blue when heated and becomes invisible again after a while (if not overly heated)
The writing is made visible by heating the paper, either on a radiator, by ironing it, or by placing it in an oven. A 100 W light bulb is less likely to damage the paper.
Friday, July 11, 2008
Wednesday, July 2, 2008
Pattern Recognition
I secretly love the strange howls the dogs give to passing sirens, the way I love the smell of skunk, eating flesh off mango stones, or shucking corn.
Oh, Harpers.
"20-year-old Kazakh supermodel Ruslana Korshunova jumped to her death from a Manhattan apartment building. “My dream,” she once wrote on a website, “is to fly.”19 Scientists found that humans laugh because they are surprised by new patterns, that they grow happier as they grow older, and that their sense of adventure is located within the ventral striatum; they also found that they can easily remember happiness and sadness, but, with the exception of some groups of Asian Americans, often have trouble recalling mixed emotions. People also sleep poorly when they eat at night, and tend to overeat as they contemplate their own deaths."
Tuesday, July 1, 2008
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