Exposition d'un nouveau principe général de dynamique,

First edition of this scarce work on mechanics by the Czech mathematician and inventor Count Buquoy (1781-1851). WorldCat locates just fourteen copies in institutional holdings worldwide (nine in European libraries and five outside Europe, all in the US).

"Buquoy was the first who investigated mechanical systems with a varying mass. In 1812 he explicitly formulated the correct dynamical equation of motion for the case when the mass of a moving object is changing. He subsequently suggested several nice concrete examples of such a motion to which he applied his new generalised dynamical equation, attempting also to solve the corresponding differential equations. In August 1815 he presented his results at the Paris Academy of Sciences (Institut National des Sciences et des Arts, Première Classe) to Laplace, Poisson, Ampère, Delambre, Arago, Cauchy, Fourier and others. Nevertheless, apart from a single short article by Poisson, his ideas did not attract attention, and they gradually became forgotten. Buquoy's general equation of motion and other explicit examples were later formulated independently by various authors. The pioneering work of Buquoy on systems of non-constant mass was rediscovered and his role in the history of physics was recognized only recently by Mikhailov. Since then it has begun to appear in some new textbooks on mechanics" (Síma & Podolsky, pp. 1037-8).