First offprint of Einstein’s important follow-up paper on field equations, 1919

Albert Einstein: Spielen Gravitationsfelder im Aufbau der materiellen Elementarteilchen eine wesentliche Rolle? [Do Gravitational Fields Play an Essential Role in the Structure of the Elementary Particles of Matter?] Sitzungsberichte der Preussischen Akademie der Wissenschaften, XX (1919). Gesamtsitzung vom 10. April. Sonderabdruck [Offprint]). Berlin: Verlag der Akademie der Wissenschaften (in commission at Walter de Gruyter [Reichsdruckerei]), 24th April 1919.

Imperial 8vo (25,4:18,2 cm). 8 pages, numbered 349-356. Letterpress on machine paper, in original publisher’s brochure on cream stock with black title printing.

First offprint in the original wrappers, of Einstein's important follow-up paper on field equations in his General Theory of Relativity.

Contents: „Einstein [in this paper] suggests that perhaps electrically-charged particles are held together by gravitational forces. (...) Thus electromagnetism constrains gravitation. This idea may be considered Einstein’s first attempt at a unified field theory.” (Pais).

Condition: A truly mint copy, probably unread.

Rarity: According to Weil early offprints of Einstein’s papers may also be qualified as original and also highly collectable editions, however they were printed in a certain, but still small print run for commercial use (mainly to sell them to fellow natural scientists): „No doubt, the first appearance in a periodical [journal issue] is the „original edition“, but I have to leave it open for collectors, librarians and others to decide whether these offprints in wrappers, mostly with a printed title on them (especially in the »Sitzungsberichte der Königlich Preussischen Akademie der Wissenschaften«) are also „original editions“. These offprints are printed from the same setting as the text, but often with new pagination.“ (p. 4). As of February 2024 RBH records only 4 copies of present offprint at auction, 2 of them are additionally marked as author's presentation copies with „Überreicht vom Verfasser“ (2023, 2006, 2002, 1999).

Reference: Boni, N.: A bibliographical checklist and index to the published writings of Albert Einstein, 111; The Collected Papers of Albert Einstein. Volume 7, 17; Shields, M. C.: Bibliographie der Schriften Einsteins. In: Schilpp, P. A.: Albert Einstein als Philosoph und Naturforscher, 120; Weil, E.: Albert Einstein. A bibliography of his scientific papers, 1901-1930, 106; Pais, A.: Subtle is the Lord. The Science and Life of Albert Einstein (2005 ed.), p. 288.