In adding a Supplement to The Robinson Telegraphic Cipher, no other change whatever has been made.

All but the supplement being printed from the same plates as the former Revised Edition.

The supplement will supply to a great extent phrases, etc., that changes in business methods and new Grades, Railroads, etc., have been called into use since the last revision.

The additions by themselves, rather than scattered through the code, will avoid danger of using a code word for the additions, with one who has not as yet received a copy with the supplement.

With the present arrangement it will at times be necessary to look in two places, for a phrase or code word, the extra turn of a leaf.

Many users of the code having written their own phrases on the blank lines, or pasted phrases over the printed ones they do not care for, but using the "Code" word for the phrase covered up. Any change in the original book would cause confusion, loss and lack of confidence.

You have probably found phrases not needed by you, and failed to find some you do want; to supply this need, write them in the blank lines. A few minutes time will do it.

To attempt to put in one Code the matter to meet all wants, the size would kill its usefulness.

Time is too valuable these days of rush, to use a dollar's worth hunting through a big code to save a few cents in Telegraph Tolls.

Better use two code words, combining the phrases of each, for even then you will seldom fail to get your Telegram inside ten words.

The All Important Thing is Safety.

Very few realize the liability of error by the receiving operator in receiving cipher or code words by sound, where the connecting words are no help.

The missing or adding of a single dot or dash, the misjudgment of a "space", may change the entire meaning.

It is therefore vital that the code words should be selected with the utmost care, and by one fully competent to judge of their fitness.

I studied nearly a year selecting a list of words I considered safe to use, analyzing every one from a telegraphic standpoint, as well as from their liability of being misread from manuscript. In many cases several words equally safe, if but one used. Cutting out the words from Webster's Unabridged Dictionary till I had between five and six thousand I considered safe to use as "code words."

Every word added, the danger of error increases, and the more words added the ratio of danger increasing in proportion.

In this selection I gave the benefit of fifteen years' personal experience as an operator and manager, over three years as operator and cipher clerk for the United States Government, and ten of the fifteen as telegraph manager on the Chicago Board of Trade.

In the majority of codes the cipher words are virtually copied as they come out of a dictionary. Many words so little in use that the sending operator for fear of sending one wrong asks to have the words rewritten, thus causing delay that may cost as much as if sent wrong.

During the past thirty-five years The Robinson Telegraphic Cipher has been, and is still in use in nearly every city and town in the United States and Canada having a telegraph office. Thousands using it, yet the errors in transmitting its code words are less even than in messages in plain English. In fact virtually nil.

Its record speaks for itself.