The invention of bifocals had been reviewed in great detail by Dr. John R. Levene in Chapter 6 of his book Clinical Refraction and Visual Science, Butterworth’s, 1977. Highly regarded as a diplomat and as a scientist, Franklin is generally acknowledged for all his ingenious contributions to many very practical inventions. He had talents and also numerous interests and his natural curiosity led to the search to discover ways to make things work better. One of his greatest innovations was “my double spectacles” and Franklin has been quite appropriately recognized and universally admired as their inventor.
Certainly among the most useful inventions of all time bifocals have serviced billions of people over the past 200 + years. Compound corrective lenses, usually bifocals or trifocals, and with increasing frequency, progressive multifocal length eyeglasses are the modern-day result of the remarkable evolution from Benjamin Franklin’s original simple and practical creation.
THE EVIDENCE SUPPORTING FRANKLIN
1). Benjamin Franklin was a hyperope who likely required eyeglasses originally in the 1730s. By the late 1750s he was usually described wearing them and they became an integral part of his face, at least for distance use. Many paintings and contemporary sketches and satirical cartoons show him represented wearing his eyeglasses. He admitted that he could not “distinguish a letter or even of large print without them”.2). The Library Company of Philadelphia, founded by Franklin and some of his friends, became America’s first lending library. In its print archives there exists a 1764 political cartoon which depicts Franklin wearing an unusual pair of eyeglasses, interpreted by some knowledgeable people as bifocals because the upper portion of each lens appears different from the lower portion. Take a close look and decide for yourself.
3). Von Rohr and several others credit optician Samuel Pierce with making bifocals for Franklin. Pierce described people wearing bifocals in 1775 and he himself may have worn them in the 1760’s. Although this is all noted in the Levene’s chapter no hard evidence is presented.
4). Mr. H. Sykes, an English optician living in Paris, with a business on the Place du Palais-Royale, wrote to Franklin April 24, 1779 and explained the delay in sending Franklin’s order, complained he was having difficulty making the eyeglasses. “I should have sent your spectacles sooner, but in compliance with your favor of the 20th inst., have cut a second pair, in which I have been unfortunate for I broke and spoilt three glasses.”Sykes had apparently damaged them while “cutting” them in half. The word “cut” is emphasized as opposed to the word “grind”. Even Sykes’ charge for this service (18f a pair) was quite excessive when compared to the normal fee of making simple ordinary glasses.
5). During his stay in Passy, outside of Paris, Franklin (serving as the American envoy to the Court of Louis XVI) described in a letter dated August 21, 1784 to his close friend and philanthropist George Whatley:
…….”I cannot distinguish a letter even of large print; but am happy in the invention of double spectacles, which serving for distant objects as well as near ones, make my eyes as useful to me as ever they were: If all the other defects and infirmities were as easily and cheaply remedied, it would be worth while for friends to live a good deal longer…..”
6). In a letter dated November 15, 1784 Whatley wrote back:
“I have spoken to Peter Dollond about YOUR invention of double spectacles, and, by all I can garner,…….”
7). Another correspondence with Whatley May 23, 1785 further explains Franklin’s basic position on this matter. Noted London optician Peter Dollond had stated they were only good for “particular eyes”. Franklin’s reply is certainly very persuasive evidence that he was the inventor:
…………..”By M. Dollond’s saying that MY double spectacles can only serve particular eyes, I doubt he has not been rightly informed of their construction. I imagine it will be found pretty generally true, that the same convexity of glass, through which a man sees clearly at distance proper for reading, is not the best for greater distances. I therefore had formerly two pairs of spectacles, which I shifted occasionally, as in traveling I sometimes read, and often wanted to regards the prospects. Finding the change troublesome, and not always sufficiently ready, I had the glasses cut and half of each kind associated in the same circle, thus
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