CH. XIV] CRYPTOGRAPHS AND CIPHERS 317 



ago by the British Museum. It was believed to be a state 

 paper of importance. It consists of a series of numbers with- 

 out any clue to their meaning, or any indication of a division 

 between words. The task of reading it was rendered the more 

 difficult by the supposition, which proved incorrect, that the 

 document was in English; but notwithstanding this, Sir Charles 

 Wheatstone discovered the key*. In this cipher a was repre- 

 sented by any of the numbers 12, 13, 14, 15, 16, or 17, b by 18, 

 19, and so on, while some 65 special words were represented 

 by particular numbers: in all about 150 different symbols were 

 used. 



The famous diary of Samuel Pepys is commonly said to 

 have been written in cipher, but in reality it is written in 

 shorthand according to a system invented by J. Sheltonf. 

 It is however somewhat difficult to read, for the vowels are 

 usually omitted, and Pepys used some arbitrary signs for 

 terminations, particles, and certain words — so far turning it 

 into a cipher. Further, in certain places, where the matter is 

 such that it can hardly be expressed with decency, he changed 

 from English to a foreign language, or inserted non-significant 

 letters. Shelton's system had been forgotten when attention 

 was first attracted to the diary. Accordingly we may say that, 

 to those who first tried to read it, it was written in cipher, but 

 Pepy's contemporaries would have properly described it as being 

 written in shorthand, though with a few modifications of his 

 own invention. 



A system of shorthand specially invented for the purpose 

 is a true cipher. Such a system in which the letters were 

 represented by four strokes varying in length and position was 

 employed by Charles I. Another such system in which each 

 letter is represented either by a dot or by a line of constant 

 length was used by the Earl of Glamorgan, better known by his 

 subsequent title of Marquess of Worcester, in 1645; each of these 



* The document, its translation, and the key used, are given in Wheatstone's 

 Scientific Papers, London, 1879, pp. 321—341. 



t Tachy-graphy, by J. Shelton, first edition 1620, sixth edition used by 

 Pepys 1641. A somewhat similar system by W. Cartwright was issued by 

 J. Rich under the title Semographie, London, 1644. 



