Cocker, Edward (1631-1675), the reputed author of the famous Arithmetick, the popularity of which has added a phrase (“according to Cocker”) to the list of English proverbialisms, was an English engraver, who also taught writing and arithmetic. He is credited with the authorship and execution of some fourteen sets of copy slips, one of which, Daniel’s Copy-Book, ingraven by Edward Cocker, Philomath (1664), is preserved in the British Museum. Pepys, in his Diary, makes very favourable mention of Cocker, who appears to have displayed great skill in his art. Cocker’s Arithmetick, the fifty-second edition of which appeared in 1748, and which has passed through about 112 editions in all, was not published during the lifetime of its reputed author, the first impression bearing date of 1678. Augustus de Morgan in his Arithmetical Books (1847) adduces proofs, which may be held to be conclusive, that the work was a forgery of the editor and publisher, John Hawkins; and there appears to be no doubt that the Decimal Arithmetic (1684), and the English Dictionary (second edition, 1715), issued by Hawkins under Cocker’s name, are forgeries also. De Morgan condemns the Arithmetick as a diffuse compilation from older and better works, and dates “a very great deterioration in elementary works on arithmetic” from the appearance of the book, which owed its celebrity far more to persistent puffing than to its merits. He pertinently adds,—“This same Edward Cocker must have had great reputation, since a bad book under his name pushed out the good ones.”