CIPHER WRITING, a method of sending important intelligence in a man ner so effectually disguised that only those for whom the news is intended can understand the meaning of what is writ ten. Till comparatively recent years diplomats, statesmen, and military or naval commanders were the principal persons compelled by circumstances to keep their affairs or their intended move ments shrouded in secrecy. So long as there was no regular postal service im portant letters were sent by courier, and thus the weightiest secrets were often at the mercy of any one inclined to be dis honest.
Hence there came into extensive use the art of writing in cipher, called also cryptography, from two Greek words Kpvirr6s, "secret," and wdOecv, "to write." Under this term are included all private alphabets, or systems of characters for the safe transmission of secrets. A fig ured cipher is one in which the letters of the alphabet are numbered, and these numbers compose the cryptogram. To insure secrecy it is, of course, necessary that the particular series of numbers chosen shall be known only to those who use the cipher. Another plan consists in choosing a certain book—a dictionary ap pears to have been the favorite—and by a simple citation of the number of the page, of the column, and of the line, sentences were constructed, the key to which was extremely difficult of discovery by one not in the secret.
The opening years of the second half of the 19th century found the world in amazement over the then recent inven tion of telegraphy. Immediately a new want made itself felt. Secrecy had been sacrificed at the shrine of speed. If the mail was slow, it afforded privacy, but the contents of a telegraphic message are of necessity known to others besides the sender and the receiver. So the diplo
mat, the banker, and the merchant soon began to send cipher dispatches. It was quickly discovered, however, that existing methods of Cipher Writing were un adapted to telegraphy; the costliness of the new invention necessitated brevity; and thus it was not long before there went whirling over the wire messages of 10 words that, properly deciphered, in cluded from 30 to 50.
A great proportion of commercial mes sages are similar in their terms, and hence it is that a single word represent ing three or four words in frequent use is the plan on which our present cable ciphers are based, whereby there is an nually a large saving in expense. Then, too, as trade increased and competition became fierce, every firm wanted its own cipher-system, distinct from any used by other houses in the same business; and reflection will enable us to appreciate the vast number of separate ciphers in use in a great commercial center like New York City. Therefore, in course of time, the preparation of cipher systems for mer chants and others using the telegraph largely came to be a regular calling.
At one of these offices a person may be accommodated with a code of from 50 to 5,000 words. Most of these codes are al phabetically arranged in parallel columns, like shipping signals—the English words and phrases in one column, and their cipher equivalents in another.
The cipher codes of the State Depart ment at Washington are frequently changed. The special code is intrusted to the personal custody of diplomatic offi cials embarking on a mission, who retain possession of it and destroy it if their lives are endangered.