New Page 2

Chapter XVI
On Simple Inverted Transposition:
Of Two Letters Taken by Themselves.

The nature of Simple Inverted Transposition is to be gathered from the sentence: However, this Transposition is called Inverted, &c. and the following sentences, in the preceding chapter. This Transposition may be accomplished by writing with two, three, or more letters. When we have occasion to write with two Transpositive letters, which are expressed together by a single device, we require a table of the sort constructed and presented by de Vigenere, pp. 184 and 238. I will append immediately to the table the explanation thereof and the method of use.

The table consists of two alphabets, to which is appended a third alphabet, accidental
thereto. These three are an interior alphabet, a middle alphabet, and an exterior alphabet,
which is the accidental one. The interior alphabet

Ch. 16. 257