O kolebanii vesov. Rech' dlja obshhego sobranija X-ogo S'ezda Russkih Estestvoispytatelej v g. Kieve (avg. 1898g.).

Folio. Autograph manuscript. 24 ff., some leaves written on both sides. Revised by the author throughout. Stored in custom-made blue half morocco solander case. The original manuscript of Mendeleev's speech on "The Oscillation of the Balance", delivered at the General Meeting of the 10th Congress of Russian Naturalists in Kiev (August 1898). In his annotated bibliography of his own works, self-compiled in 1899, Mendeleev writes: "Predmet schitaju ochen' vazhnym i interesnym" ("A subject I find very important and interesting"). After the end of his teaching career at the University of St. Petersburg in 1890, Mendeleev was variously employed by the government bureaucracy. From 1892 on he was "concerned in the regulation of the system of weights and measures in Russia, a task that he discharged 'with enthusiasm, since here the purely scientific was closely interwoven with the practical.' In 1893 he was named director of the newly created Central Board of Weights and Measures, a post which he held until his death, and in connection with which he frequently traveled abroad" (DSB IX, 292). - "The great importance of Mendeleev's work", write Kayak and Smirnova, "was that in his approach to the development of the theory of balances and methods of accurate weighing he took into account the physical essence of the phenomena investigated, whereas many investigators before and even after him attempted to solve all the problems on the basis of purely mechanical conceptions [.] Mendeleev's interest in balances as the most important instrument in physical and chemical investigations was manifested from the very beginning of his scientific work. Long before his move to the Depot of Standard Weights and Measures he devoted much attention to the perfection of balances, and methods of accurate weighing. In 1861 Mendeleev succeded in observing the oscillations of balances from a distance, thereby eliminating the influence of the heat radiated by the observer on the balance; he also proposed the use of a heat distributor made of copper for a balance beam. Mendeleev's most important work on the development of the theory of balances and methods of accurate weighing was made at the Principal Bureau of Weights and Measures, where he took upon himself the entire responsibility for organizing and equipping the weight laboratory" (p. 25). - Occasional insignificant edge defects, but altogether a very well preserved manuscript. Includes a copy of the published text. - Published: Sochineniya 7, pp. 577-591. Reference: Sochineniya 25, p. 752, no. 275. - Cf. L. K. Kayak and N. A. Smirnova, Theory of balances and accurate weighing in the investigations of Mendeleev and later developments, in: Izmeritel'naya Tekhnika 9 (Sept. 1969), pp. 25-28.