Herschel's graph

Herschel's graph This graceful graph is a favorite example that accompanies texts on graphs. It is triangle-free (its shortest girth is of length 4), and it is 2-colorable.

Help! What is the origin of this graph? [note].

The harmonic evolution digraph consists of:
 Loops= 4 L1 + 6 L2
Tree= T13 * T22

Note

Herschel is the surname a family of British astronomers. This includes Sir William Herschel (1738-1822), who discovered Uranus (1781) and cataloged numerous double stars and nebulae. His sister Caroline Herschel (1750-1848) published a star catalog, and his son Sir John Frederick William Herschel (1792-1871) discovered another half-thousand nebulae and conducted research on astrophysics, light, and photography.

Is the author the Herschel graph related to any of the above? ("Graph Theory 1736-1936" by N.L.Biggs at al., does not mention "Herschel's graph," but its bibliography includes a 1862 paper on Hamilton's icosian game by a certain A.S. Herschel. The date of publication does not seem to match Sir William-astronomer's life span. Please send me a note if you can cast some light on this puzzle.

Remark: Discovery of Uranus was a shock to the astrological systems. The East still ignores it. The West absorbed it, gave it a symbol and associated with unpredictability, modern science, anarchy and the destruction of the established order. This is partially credited to the French Revolution that occurred a few years after the discovery. The symbol -- another "Herschel's graph" -- is modeled after "H".

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