England, 1797. Sterling silver ring temple spectacles, bifocal lenses. Contained in porbeagle case. One of the most ancient pieces with bifocal lenses after Benjamin Franklin's invention in 1785. In a letter written in May 23rd, 1785 Franklin is finally pleased to have a single pair of glasses that allowed him to see both distance and near. These were two lenses with different powers, half-moon shaped and placed together in the same ring.