Barbara McClintock (1902-1992), the cytogeneticist who won the 1983 Nobel Prize for Physiology or Medicine, used this wide field binocular to examine the morphological mutations in kernels of corn. It is a model AKW with drum nosepiece, rack-and-pinion, and square glass stage. The inscriptions read “BAUSCH / & LOMB/ OPT. CO.” and “PAT. 1,622,350.”
Ref: John C. Sabel, “Binocular Microscope,” U.S. Patent 1,622,350 (March 29, 1927).
Bausch & Lomb, Scientific Instruments (Rochester, N.Y., 1939), pp. 57-58.