BOLTZMANN, Ludwig (1844-1906, physicist). Autograph letter signed ('Ludwig Boltzmann') to the philologist Wilhelm von Hartel, Graz, 25 May 1885, thanking him for sending a telegram with news of his election to the Imperial Austrian Academy of Sciences, 'Ich bekam es schon 2½ Uhr und da, wie ich glaube, die Sitzung erst 1½ Uhr begann, so begreife ich fast gar nicht, wie ich so schnell Nachricht haben konnte', one page, 8vo, envelope. Provenance: Stargardt sale, November 1983; the Albin Schram Collection. Boltzmann occupied the chair of Experimental Physics at Graz University. He was a founder of the fields of statistical mechanics and statistical thermodynamics, and an important early advocate for atomic theory.