The Ethereum 1 book has an actual Ethereum (ETH) address hidden within its puzzles. A cryptocurrency address is a unique string of various letters and numbers. The puzzles in this book form one of three cryptocurrency address strings. Whomever decodes and solves the puzzle first, and is the first to respond with the correct solution, will have the Ethereum (ETH) cryptocurrency sent, by the author, to the successful reader's respective receiving account which they can submit through email. The intent of this book is for the reader to discover the Ethereum cryptocurrency address. This book is one in a series of 3 puzzle books, which include the Bitcoin 1 book and the Ripple 1 book.