For this purpose let the telegraphic characters representing particular letters be transposed and interchanged. Then the representative of _a_, in the _permanent_ alphabet, may be represented by _y_, or _c_, or _x_, in the _secret_ alphabet; and so of every other letter. As there are twenty-seven characters in the telegraphic alphabet, they can, by transposition, furnish six hundred and seventy-six different kinds of secret alphabets; nearly two for every day of the year. Two persons have agreed to use, in their telegraphic correspondence, the secret alphabet. From the six hundred and seventy-six combinations, they have selected one for each day in the year, and given each their particular date. In the course of their business, it becomes necessary on the first of July, for one to transmit important information to the other. He then refers to the telegraphic book, for the alphabet belonging to that date, and from it writes his communication, as follows: _The firm of G. Barlow & Co. have failed._ He runs his eye along the alphabetical column for _t_, and finds that for the first of July it is _e_, that _h_ is _j_, _e_ is _n_, and in the same manner, he proceeds with the remaining letters of his message, which, when completed, reads as follows: _Ejn stwz ys & qhwkyf p iy jhan shtknr_. As every person employing the telegraph has his name, occupation and place of business registered in the record book of the office, with his telegraphic number, we will suppose, that _Mr. Hammond, Builder, 57 Anson-st. Philadelphia_, sends the above communication to the office for _Messrs. Talford & Co. Lumber Merchants, 41 Bradford-st. New York_. In the record, the former name is numbered 14; and the latter 31. The private message is then directed thus, _No. 14 to No. 31_, and reads thus: Mr. Hammond, &c. sends the following communication to Messrs. Talford & Co. &c. “The firm of G. Barlow & Co. have failed.” This message, in substituted characters, is copied at the receiving station, and immediately delivered. The messenger returns with the following: _Syw fjhe hzyxce._ To which is prefixed _No. 31 to No. 14_. This is sent to Mr. Hammond, who, on translating it, discovers that it must be answered by figures. He then refers to the secret numerals, under the date of the first of July, and finds the private numerals required are 897, 312, adding to it a few letters, when it reads thus, _No. 14 to No. 31, 879, 312 rykkm_. If it should happen, that on the 6th of December, or 13th of May, it was necessary to send a private communication, the secret alphabets of those dates are used, and so for any date of the year.