Page:Telegraphic Code to Insure Privacy and Secrecy in the Transmission of Telegrams.djvu/10

 A copy of this Code has been sent to, and will remain with, each bank in New York City, whose address and "cipher-word" follows hereafter.

A copy has likewise been sent to each bank which is a member (in 1822) of the Clearing House in Chicago, St. Louis, New Orleans, and San Francisco.

This Code is stereotyped and no changes will be made at any time.

A banker in the West should prepare a list of irregular numbers, to be called "shift-numbers," such as 483, 281, 175, 892, &c.

The differences between such numbers must not be regular.

When a shift-number has been applied, or used, it must be erased from the list and not used again.

A copy of the list is to be sent to the New York Banker, who prepares a different list and sends copy thereof to the Western Banker.

Each party should enter his own list in black ink in a book, and copy his correspondent's list in red ink upon the opposite page; thus the black figures will denote his "sending numbers," and the red figures will denote his "receiving numbers."

Having occasion to telegraph an order requiring the payment of money, and knowing that an English dispatch would receive no attention, the Western banker will write his dispatch on a sheet of paper, leaving a few lines blank between the written lines.

He will then find his first word in this Code, and copy upon the sheet of paper its number, placing the number under the word.

Under said number (which we will call the "serial-number") he will place the first 44 shift-number" (say 483). He will then add the two numbers and find their sum, which he will write down.

Underneath this new sum, or number, he will write the "cipherword" which he shall find in the Code standing alongside of said sum.

Thus he gets the first cipher-word for his telegram.

To the appropriate 44 serial number "of the second word he will add the second "shift-number" (say 281), and, finding their sum, he will take the cipher-word which is found opposite said sum.

He will follow the same plan with the remaining words.

The receiver will reverse the operation, writing down the first cipher-word of the telegram; under it placing its "serial number," and from that deducting the first "shift number" (say 488), thus finding the "serial number" of the first English word transmitted.

From the serial number of the second cipher-word in the telegram he will deduct the second "shift-number" (say 281), thus finding the serial number of the second English word transmitted.

For many telegrams it will suffice that the common English words be used with a "test word" that shall indicate that the dispatch was genuine as sent. Economy and much safety can also be secured by using a "test word" and placing the rest of the message in "plain cipher"—that is, using the Code as printed without any "shifting."

The sender will, in such cases, take the two right-hand figures of his first "shift-number," and use the test word indicated by such two figures; thus he will use the test word "Abstruse" if his first key is 483, and place the rest of the message in English or in "plain cipher."

The receiver will note that a "test word" is used, and that its number is the same as the two right-hand figures of the key (or "shift-number"), which is then available.

Said "shift-number" must, of course, be then erased by both sender and receiver, for it is void for further use.

Abstruse Foredated Furuncle Admirers Disgusted

Abstruse: Extended for eight days.