Brown Bag Lecture: “Molecules in Biology before Molecular Biology: Imagining Molecules under Polarized Light, 1910–1939”

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Date: November 4, 2014
Time: 12:00 to 1:00 p.m.

315 Chestnut Street
Philadelphia, PA 19106

Event Type: Open to the Public
Fee: Free
RSVP Online: No Registration Required

A talk by Daniel Liu

What does “life” look like? If you look at a cell under a microscope, can you see the molecules that make up its membranes, its genes, chromosomes, mitochondria, and cytoplasm? In the 1920s not only would the vast majority of biologists answer with a definite “no,” but a few would go so far as to deny the very relevance of studying something as small as a molecule in living organisms. This denial  was not due to any ignorance about chemistry or physics, but rather came from the dizzying array of new chemical ideas and theories of the 1910s and 1920s, which biologists tried to incorporate into existing and diverse biological theory. This lecture will introduce a few biologists who argued, against the prevailing wisdom, that living cells had an unseeable molecular structure. With x-ray crystallography in its infancy and electron microscopy still two decades away, this lecture will look at how these biologists turned instead to the polarized light microscope—a precision instrument that nonetheless demanded a great deal of interpretation, inference, and guesswork to make conclusions about the nature of life and living matter. Although they were never successful in promoting polarization microscopy, their ideas about a molecular structure to living matter would spread to other biologists largely through their imaginative use of analogies and illustrations.

Daniel Liu is a PhD candidate studying the history of modern biology at the University of Wisconsin–Madison in the Program for the History of Science, Medicine, and Technology. His dissertation, “Molecules in Biology before Molecular Biology, 1920–1950,” examines how biologists coped with the revolutionary changes in theories of atomic bonding and molecular structure in physics and chemistry in the first decades of the 20th century and how they used these new ideas to reshape ideas of life and living matter.

About Brown Bag Lectures

Brown Bag Lectures (BBLs) are a series of weekly informal talks on the history of chemistry or related subjects, including the history and social studies of science, technology, and medicine. Based on original research (sometimes still in progress), these talks are given by local scholars for an audience of CHF staff and fellows and interested members of the public.

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