CH. XIV] 



CRYPTOGRAPHS AND CIPHERS 



299 



be a great disadvantage if time in sending the message was of 

 importance. 



Another method, essentially the same as the grille method, 

 is to arrange that every nth word shall give the message, the 

 other words being non-significant, though of course inserted as 

 far as possible so as to make the complete communication run 

 as a whole. But the difficulty of composing a document of this 

 kind and its great length render it unsuitable for any purpose 

 except an occasional communication composed at leisure and 

 sent in writing. This method is said to have been used by 

 the Earl of Argyle when plotting against James II. 



Third Type of Cryptographs. A kind of secret writing 

 which may perhaps be considered to constitute a third type of 

 cryptograph is a communication on paper which is legible only 

 when the paper is folded in a particular way. An example is 

 a message written across the edges of a strip of paper wrapped 

 spiral-wise round a stick called a scytale. When the paper 

 is unwound and taken off the stick the letters appear broken, 

 and may seem to consist of arbitrary signs, but by wrapping 

 the paper round a similar stick the message can be again 

 read. This system is said to have been used by the Lace- 

 demonians. The concealment can never have been effectual 

 against an intelligent reader who got possession of the paper. 

 As another illustration take the appended communication which 



is said to have been given to the Young Pretender during his 

 wanderings after Culloden. If it be creased along the lines 

 BB and GO {GG being along the second line of the second score), 

 and then folded over, with B inside, so that the crease G lies 



