One striking feature of old glasses frames from the Revolutionary period is that high quality metal spectacles frames were no longer exclusively imported. Lenses were still mostly from Europe or England, since the very low cost and extremely high quality of lenses from the Old World made it difficult for local artisans to compete – the barriers to entry to the market were very high.
However, you can find even fancy silver antique eyeglass frames from the Revolutionary period which bear the inscription of American silversmiths, rather than this being the exclusive preserve of British artisans. The inscriptions tend to be somewhat more matter of fact; the name of the silversmith is given, as well as the town and state, often in an abbreviated form.
This is a rather less decorative approach than the hallmarks and flowing monograms of the Englishmen of the period (whose old glasses frames are also still very common in the Colonies or the nascent United States), but it is very useful in discovering whether a pair of frames was made in America itself. Naturally, most of these old glasses frames were fashioned in the major cities.
Early ergonomics in Revolutionary old glasses frames
The science of ergonomics was largely unknown (and completely unnamed) at the time of the American Revolution. However, some of the improvements introduced at this time show that better crafting techniques were making it possible to increase the comfort and convenience of old glasses frames even while the materials used to make them remained the same.
Early examples of oval and octagonal spectacles from the Revolutionary era workshops featured the same thick, bulky, heavy metal construction found on 17th century spectacles. These thick wires – whether in the form of eyerims, bridges, or temples – added to the weight of the glasses and made them clumsy and somewhat uncomfortable to wear for long periods.
During this time, however, old glasses frames became slimmer, lighter, and more graceful. They fitted better to the human face and weighed less, making them easier to wear for an extended period. Thinner metal is also a highly visible clue allowing you to instantly see that a pair of early spectacles is probably from the time of Washington instead of Mather.
This did not occur in a day, of course, and since old glasses frames were still made by individual artisans, there was plenty of room for variation. This is part of what makes collecting or studying the eyewear of the past so intriguing, however – the fact that detective work and reasoning are needed to ferret out a piece's provenance as much as a list of major clues.
Focal length markings on old glasses frames from America
The old custom of marking the focal length of the lenses in inches on the old glasses frames in which they were mounted continued into the Revolutionary period. However, several additional focal length systems were in use at the time, so the number on the glasses requires verification with a lensometer if you want to determine exactly what the focal length is (and what type of measurement has been engraved into the metal).