[EULER (Leonard). Letters to a German princess on various subjects of physics and philosophy. Berne, by the typographical society, 1778. 3 vol. in-8 calf-race, spines smoothly decorated (contemporary binding). 19 folding plates in fine. Leonhard Paul Euler (Basel 1707 - St. Petersburg 1783) was a great mathematician and physicist who made important discoveries in infinitesimal calculus and graph theory. The princess to whom these letters are dedicated is the princess of Anhalt-Dessau, niece of the king of Prussia. She received Euler around 1760-1762. Very worn bindings. (Barbier II, 1223.)

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