en
Martin Gardner

Codes, Ciphers and Secret Writing

Kitap eklendiğinde bana bildir
Bu kitabı okumak için Bookmate’e EPUB ya da FB2 dosyası yükleyin. Bir kitabı nasıl yüklerim?
“A fascinating, challenging book.” — A. L. A. Booklist. Experiment with cryptography — the science of secret writing. Cipher and decipher codes: transposition and polyalphabetical ciphers, famous codes, typewriter and telephone codes, codes that use playing cards, knots, and swizzle sticks…even invisible writing and sending messages through outer space. Hours of intrigue and challenge. 45 diagrams.
Bu kitap şu anda mevcut değil
181 yazdırılmış sayfalar
Yayınlanma yılı
2013
Bunu zaten okudunuz mu? Bunun hakkında ne düşünüyorsunuz?
👍👎

İzlenimler

  • Dannibir izlenim paylaşıldı4 yıl önce
    👍Okumaya değer
    🎯Değer

    Fascinating 🤩 Special thanks for all the illustrated cipher examples .

Alıntılar

  • Dannialıntı yaptı4 yıl önce
    Not long ago someone asked the famous Chinese physicist Chen Ning Yang what we should do if we ever received an unmistakable radio message from outer space. His reply was:
    “Don’t answer.”
  • Dannialıntı yaptı4 yıl önce
    JEFFERSON’S WHEEL CIPHER
    In the picture, the wheels have been set so that the horizontal line of letters, above the cross-bar, reads: “Have just reached eastern edg.” These are the first 25 letters of a message. The encoder copies down any other horizontal line of letters. The decoder sets the wheels to align the cipher text, then he looks around the cylinder for a line which makes sense. All the other lines, Jefferson wrote, “will be jumbled and have no meaning, so that he cannot mistake the true one intended.”
  • Dannialıntı yaptı4 yıl önce
    Porta’s Digraphic Cipher
    A digraphic cipher is one in which pairs of letters, instead of individual letters, provide the basis of the cipher text. In the Porta Cipher, a single symbol is substituted for every pair of letters in the message. The method was invented by Giovanni Battista Porta, an Italian writer, scientist and magician. At the age of 28 he published (in 1563) a delightful book on codes, which included this one. It is the first known digraphic cipher.

Kitap raflarında

fb2epub
Dosyalarınızı sürükleyin ve bırakın (bir kerede en fazla 5 tane)