First edition of the first textbook on theoretical mechanics based on Leibniz's calculus, important for containing the first published discussion of the kinetic theory of gases. "This textbook concerned advanced mechanics in the modern sense and was considered an important work, very favorably reviewed by Leibniz himself in the Acta Erudorum" (Fellmann in DSB). “The beginning of the kinetic theory of gases is usually assigned to the year 1738, when Daniel Bernoulli's “Hydrodynamica” appeared in Strasbourg. The famous tenth section of this book pursued some of the consequences of the hypothesis that “elastic fluids” consisted of innumerable tiny, rapidly moving particles.[However, an] earlier attempt dates back to 1716, and is found in the "Phoronomia" of Bernoulli's compatriot, Jacob Hermann: Hermann's chapter XXIV is the first attempt to deal mathematically with the relations between heat and motion. The intuition that the speed of particles must be squared off is particularly noteworthy, but perhaps no more so than the assumption that their speeds will not all be the same, so an average must be taken" (Knowles Middleton). "In 1716, the Swiss mathematician Jakob Hermann (1678-1733) published his book on theoretical mechanics, Phoronomia, in which he proposed the first precise measurement of the heat of molecular motion.