THERMAL CONDUCTIVITY

SMOLUCHOWSKI, MARIAN.

Sur la conductibilité calorifique des corps pulvérisés (+) Études sur la conductibilité calorifique des corps pulvérisés (suite).

Cracovie, Imprimerie de L'Université, 1910 + 1911. 8vo. In the original printed wrappers. Two offprints from "Bulletin de L'Académie des Sciences de Cracovie", Mai, 1910 & Octobre, 1911. Both very fine and clean. Pp. (2), 130-53; Pp. (1), 549-57.

Scarce offprint of Smoluchowski's important paper in which he documented that a layer of smooth spherical particles in vacuum may be used as an effective thermal insulator.

"This was discovered by M. Smoluchowski some forty years ago. He investigated both theoretically and experimentally the thermal conductivity of powders, and concluded that filling the space between the walls of a Dewar vessel with a suitable powder would provide improved insulation by reducing the convective currents as well as the radiation and, moreover, would improve the vacuum by absorption. His application for a patent resulted in a long argument with the German Patent Office, whose examiners were reluctant to admit that any material agent could provide a better insulation than 'absolute' vacuum. At that time a large metallic Dewar vessel with its interstice filled with powdered active carbon was built at the Physical Institute of the University in Lwów, and showed the expected high insulating properties." (Klemensiewicz, Thermal Conductivity of Powders)

Order-nr.: 48711