Benjamin Franklin, American statesman and scientist, is attributed with 'inventing' the double-lensed spectacles (bifocals) to remedy his own long and short sightedness. It is reputed that whilst in Paris, from 1784 to 1789, Thomas Jefferson, later President of the USA, discussed these with Franklin as he too had the same problem. The spectacles offered here are very similar to spectacles Thomas Jefferson commissioned in America in 1806 from John McAllister - the founding father of the profession of opticianry in America. In his letters to John McAllister regarding his commission Jefferson wrote: "Those who are obliged to use spectacles know what a convenience it would be to have different magnifiers in the same frame. Dr. Franklin tried this by semicircular glasses joined horizontally, the upper & lower semicircles of different powers, which he told me answered perfectly ...". Jefferson drew the type of spectacle he required and described it: ".. each eye glass is composed of 2 semicircular lenses, the lower of a greater magnifying power than the upper, that is to say, of the next No.s of the upper one. A compleat set of half glasses to be sent, from the magnifier adapted to the first use of spectacles, to that suiting the oldest eyes, all fitting exactly the frames".