Secret codes
By: by Robert Jackson.
Series: A Quarto children's book; Action books; Action books (Philadelphia, Pa.)
Publisher: Running Press
Published: 2002
Place of publication: Philadelphia
Language: eng
Number of pages: 32
Subjects: Cryptography -- Juvenile literature; Ciphers -- Juvenile literature; Cryptography; Ciphers
Genres: Juvenile literature.
Notes: Activity kit (29 cm. x 20 cm.) includes two sets of semaphore flags, two Jefferson wheels, two sheets of Braille stickers, two Morse code units, two wires for Morse code units, and instructions.