How to Write and Decode Secret Messages (Codemaster)
By Marvin Miller.
Description
As featured in "Boys' Life" magazine, here are more secrets from the Codemaster. Such as baffling parents with the Ogham Code; crossing siblings' wires with the Telephone Code or mixing them up with the Scramble Code. This book contains 14 new tricky codes all designed to help readers keep their secrets safe. - from Amzon
ISBN(s)
0590373889, 9780590373883