448 THE CENTURY, 



ing with a hook, it can easily be attached to any ele 

 vated place, and on pulling the pole, each part separates, 

 falling at once into the form of a ladder with rope sides. 

 Bourne s 62nd Device, in his &quot; Inventions, or Devices,&quot; 

 1578, is &quot; How for to make a scaling ladder.&quot; 



Van Etten, 1653, gives for his lllth Problem, &quot;To 

 make a Ladder of Cords, which may be carried in ones 

 pocket : by which one may easily mount up a wall, or tree 

 alone.&quot; It consists simply of two pulleys, with &quot; a cord 

 of an half inch thick (which may be of silk, because it 

 is for the pocket),&quot; having a staff at one end to sit upon. 

 The author gravely concludes, &quot; This secret is most ex 

 cellent in warre, and for lovers, its supportablenesse 

 avoids suspition.&quot; See page 248. 



Among Friar Bacon s inventions, the following is re 

 corded in the fourth chapter of his u Discovery of the 

 Miracles of Art, Nature and Magick,&quot; 12mo. published 

 in 1659 : &quot; It is possible to invent an Engine of a 

 little bulk, yet of great efficacy, either to the depress 

 ing or elevation of the very greatest weight ; which 

 would be of much consequence in several accidents $ 

 for hereby a man may either ascend or descend any 

 walls, delivering himself or comrades from prison ; and 

 this engine is only three fingers high and four broad.&quot; 



5 1 - 



A Rule of Gradation, which with 

 eafe and method reduceth all things 

 to a private correfpondence, moft 

 ufeful for fecret Intelligence. 



\A Eule of Gradation^] Probably some scheme 

 which appeared to be capable of indefinite multiplica 

 tion, the object of the secret correspondent always being 



