Four sets of optometrists trial lenses with key trademark. Celluloid with 2×6 and 2×7 pairs of lenses, all in good condition and marked 1/2 to .6, 0.7 to .12, 1 to 4, and 5 to 11.. The case is very distressed and lid detached.
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Fletcher Wallis sells objects and books relating to the history of science, medicine and technology from his unit at Admiral Vernon Arcade Portobello Road. He publishes books through Vernier Press, including Antique Medicine Chests, and Corkscrew Patents from 1795. He has been dealing for thirty five years.