Berlin, Königliche Akademie der Wissenschaften (Georg Reimer), 1893. 8vo (26.5 x 19.0 cm). 8 pp. [numbered 55-62]. Original printed wrappers.

A very important contribution to physics (which contributed to his becoming a Nobel laureate) written by the German physicist Wilhelm "Willy" Carl Werner Otto Fritz Franz Wien (1864-1928). "In 1893 Wien stated his displacement law of blackbody radiation spectra at different temperatures. It was [Wien's] idea to use as a good approximation for the ideal blackbody an oven with a small hole. Any radiation that enters the small hole is scattered and reflected from the inner walls of the oven so often that nearly all incoming radiation is absorbed and the chance of some of it finding its way out of the hole again can be made exceedingly small. The radiation coming out of this hole is then very close to the equilibrium blackbody electromagnetic radiation corresponding to the oven temperature" ( MacTutor History of Mathematics Archive). Published in the academy's Sitzungsberichte, 1893 VII, published on 9 February, together with the unrelated publications V and VI. Uncut. A very good, unmarked copy.