“Such charlatans are the pests of science, and speculators on the credulity of society. “Mr. C. feels assured that his friends, and the public generally, will remark the necessity there is for some one, practically acquainted with the science of optics, to come forward and state the real facts of the case, at a time when bombast and chicanery, supported by the most shameless falsehoods, are put forth by itinerant hawkers and pedlars—the pretended discoverers of a superior method of constructing glasses for spectacles. He is anxious to expose such deceptions, and to protect the Spectacle wearer from the gross frauds and impositions continually practised in the sale of Spectacles at enormous prices, although made of the cheapest material, and in the most inferior manner. “Such Spectacles are productive of endless annoyance to the wearer; and, instead of rendering any assistance are instruments of torture, producing the most serious consequences to the sight, owing to their imperfect construction and the misapplication of their powers to the purposes required. “Persons requiring Spectacles are earnestly recommended to seek advice and assistance from opticians or their agents, of known respectability and experience, who are capable of judging what kind of lenses are necessary in each particular case: and to avoid those charlatans whose ignorance of optics is only equalled by their impudence, in obtruding themselves into houses, and alarming the occupiers by declaring that they perceive serious defects in their eyes, the formation of cataract, incipient blindness, &c., in order to give an exalted idea of the value of the remedies they offer.” * * * * * “T. H., Watch and Clock maker, agent to Cox, optician of London, begs to caution his friends against the impositions of itinerant hawkers, who boast of exalted patronage, wonderful discoveries, and superior skill in optics, professing to suit the sight by merely examining ‘the figure of the eye.’ Such individuals frequently enter into respectable houses, and terrify ladies and gentlemen by declaring that they perceive serious defects in their eyes, and, of course, that nothing can avert the evil but their wonderful Spectacles; sometimes pretending that their only motive in calling is from their wish to relieve mankind from the chances of losing their sight, and to enable them to see as well at fourscore years of age as at twenty, while their main object is to fill their pockets at the expense of those who have fallen into their snare. “The fallacy of their statements may always be ascertained by the parties taking medical opinion of known value, and consulting a respectable optician.