E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
The alphabet - book, which was a thin board of oak about nine inches long and five or six wide, on which was printed the alphabet, the nine digits, and sometimes the Lords Prayer. It had a handle, and was covered in front with a sheet of thin horn to prevent its being soiled; the back-board was ornamented with a rude
sketch of St. George and the Dragon. The board and its horn cover were held together by a narrow frame or border of brass. (See CRISSCROSS ROW.)