My object has been to provide the public with a compendium of sound and standard information on this most interesting and essential subject, in order that, possessing themselves of the truth, and becoming conversant with the real merits of the question, they may no longer be the victims of ignorant, designing, and knavish speculators, who so mercilessly practise on their credulity. I have freely availed myself of facts and observations with which I have become familiar in the course of my own experience and connexion with an establishment of more than one hundred years’ standing, and, at the same time, have endeavoured to condense in one publication the essence of many voluminous treatises. “It is only by condensing, simplifying, and arranging in the most lucid manner possible, the acquired knowledge of past generations, that those to come can be enabled to avail themselves to the full of the advanced point from which they will start.” I have only to add, that though I would not desire to offend the critical acumen of any of my readers, yet, having but little leisure, and those moments of rest being snatched from the busy whirl of commercial pursuits, I have been much more anxious to give solid information in language universally understood, and divested of technicalities, than to employ nice set terms, chosen to please the critic’s curious ear. GEORGE COX. The first edition of this work having found a ready sale, spite of all the opposition and abuse lavished against it by the itinerant _opticians_, I have reprinted it with such improvements as the kindness of friends and my own experience have suggested. 128, HOLBORN HILL, LONDON, _January, 1844_. Reviewers’ Opinions of this Work. “The information which this little book contains is really very good and very applicable to the instruction both of the short-sighted, who never reflect before they buy, and of the very long-sighted, who, from excess of cunning in the search of great bargains, are, like our friend Moses in the Vicar of Wakefield, open to very _gross_ impositions in the matter of spectacles and their very _chagrin_ cases. Those who are not opticians or oculists will do well to read the book before they commit themselves in the purchase of glasses either from itinerant or stationary quacks. But this is not all: though a simple monograph of the frauds of one trade, the book may be generalized into “a manual of the whole art of puffing,” and an exposure of the silly credulity of the public in all its branches. Mr. Cox also discloses some of the machinery of newspaper puffing in a way which almost tempts us to claim it as “our thunder,” it is so much in unison with our published opinions on the subject.” _Athenæum._