Facsimile of LJS 423, Dos discursos de la cifra

http://openn.library.upenn.edu/Data/0001/html/ljs423.html

Two works on ciphers. The first is more theoretical and describes ciphers based on subjects such as arithmetic, non-Roman alphabets (Greek, Hebrew) and writing systems (Egyptian, Chinese, Japanese, the writing of Indians of New Spain), astrology, musical notation, geography, currency, orthography, armorials, emblems, and enigmas. The second is a technical description of 24 different methods of enciphering and deciphering, using numerous tables, volvelles, movable sleeves, and grilles. Most of the entries in the index at the end of the manuscript (p. 165-166), which is in the same hand as the text, refer to subjects in the first work. Written by a cryptographer in the service of Martin de Cordova, viceroy of Navarre (p. 5), and dedicated to Juan Fernandez de Velasco, Condestable de Castilla (p. 3), a Spanish official who held government posts in Italy.