Smithsonian museums continue to be closed to support the effort to contain the spread of COVID-19. Read a message from our director, and check our website and social media for updates.



<< >>
Usage conditions apply
Barbara McClintock (1902-1992) used this microscope in the 1940s and 1950s for research on transposing genetic elements or “jumping genes” in maize. In this process, segments of DNA jump from one location on a chromosome to another. When Dr. McClintock published her results, she met with skepticism from many fellow geneticists. However, in 1983 she was awarded the Nobel Prize for her work. It was eventually determined that these elements are found in virtually all living organisms.
This instrument, made by Bausch & Lomb Optical Co., is fitted with a circular mechanical revolving stage designed specifically for photomicrography. Dr. McClintock gave the microscope, and its set of apochromatic lenses, to Dr. Joseph C. Gall of the Carnegie Institution in Washington, D.C. in the summer of 1977. She told him she no longer needed it and wanted it to be in safe hands. In 1993 the Carnegie Institution donated the instrument to the Smithsonian Institution.
Currently not on view
Object Name
date made
ca 1940
Bausch & Lomb
place made
United States: New York, Rochester
Physical Description
metal (overall material)
average spatial: 31.1 cm x 17.7 cm x 19 cm; 12 1/4 in x 6 15/16 in x 7 1/2 in
ID Number
catalog number
accession number
Credit Line
Carnegie Institution of Washington
Science & Scientific Instruments
See more items in
Medicine and Science: Biological Sciences
Artifact Walls exhibit
Science & Mathematics
Data Source
National Museum of American History
Nominate this object for photography.   

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.


Add a comment about this object