A Five-Minute History of Knot Theory

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James Clerk Maxwell attempted to understand how three rings of ether would pass through each other. On October 6, 1868, he wrote to Kelvin: "[Helmholtz's] 3 rings do as 2 rings in his own paper that is those in front expand and go slower those behind contract and when small go faster and thread through the others. I drew 3 to make the motion more slow and visible, not that I have solved the case of 3 rings more than to get a rough notion about this case and to make the sum of the three areas [constant] I have made them fat when small and thin when big." [Maxwell's lack of punctuation was not typical of his writing, which was generally excellent.] Maxwell drew the figures to be viewed on a zoetrope ("wheel of life") of his own design. The Cavendish Museum of Cambridge University owns the device.

This PDF contains a photograph of the Zoetrope created by James Clerk Maxwell reproduced from The Scientific Letters and Papers of James Clerk Maxwell (Harman, P. M. "Book Review: The scientific letters and papers of James Clerk Maxwell. Volume II, 1862-1873/Cambridge U Press, 1995." The Observatory 116 (1996): 44.), and a photograph of Professor Gordon Squires and Daniel Silver in 1996, during a visit to the Cavendish Museum of Cambridge. At that time, Professor Squires was the museum curator. Photo of Professor Squires and Dr. Silver was taken by Susan Williams.

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Please click on the supplemental content in the "Additional Files" section below to see James Clerk Maxwell's hand-drawn zoetrope illustration of three smoke rings.

Copyright is owned by Cavendish Museum and is reproduced here with their permission.

three rings.gif (2537 kB)

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