Cipher

si'fer, a method of sending written information in disguise. Spies sending intelligence of the movement of armies, orders sent to generals or naval commanders in foreign waters, and communications between governments and their foreign representatives are usually in cipher to prevent their being understood by unauthorized persons. In the Russo-Japanese War the Russian generals sent home their reports in cipher. They were translated in the war office, then laid before the czar. When the Russian peasants were shot down in the streets of St. Petersburg the Russian minister at Washington received a telegraphic account in cipher. If countries are at peace international courtesy requires the transmission of cipher dispatches without scrutiny or delay.

One of the simplest ciphers is the use of a dictionary. Thus: "9-3-685, 9-2-7024, 9-1-2657," referring to word, column, and page of the Century, would be deciphered to mean "bring your gun."

If it be desired to send the following message: "Owls meet by old oak at six," it may be done in a number of ways. We may use the letters that proceed the real letters, assuming that z preceeds a, thus: "n v k r ld d s a x n k c n z j z s r h w."

The letters that follow the real letters may be used thus: "p x m t n f f u c z p m e p b l b u t j y."

The words may be spelled backward, but this cipher is too easily read: "slwo teem yb dlo kao ta xis."

It is said that time, skill, and patience, with plenty of messages at hand, enable an expert to unravel any system of cipher ever invented. In his Gold Bug, Edgar Allen Poe gives a most ingenious account of the unraveling of a cipher scroll left by an old pirate to indicate where his treasure lay buried.

Modern cipher is known usually as a telegraphic code. The sender and receiver agree on a set of words and meaning. Each keeps a copy. Thus Hamstrung bolo may mean "Elevators are heavily loaded. Sell 600,000 bushels regardless of price," Gopher flag may mean "The enemy are digging mines under our largest battery. We must surrender within a week." In the first message, economy may be the motive for using a code, as telegrams cost by the word. In the second, secrecy is evidently desirable. When mere economy is desired, the sender uses usually what is known as the commercial code, a standard cipher dictionary, a copy of which is kept in all large commercial establishments and at telegraph offices. The United States government uses the Western Union code for ordinary messages. A private official code is used by the Department of State for diplomatic messages.

See Cobalt