HUBBLE, Edwin (1889-1953). "A Relation between Distance and Radial Velocity among Extra-Galactic Nebulae." Offprint from: Proceedings of the National Academy of Sciences. Volume 15, No. 3. [Washington, D.C.:] Carnegie Institution, 1929.
8o (258 x 175 mm). (One or two tiny marginal tears.) Original brown printed wrappers (fore-edge with tiny tear). Provenance: Herbert McClean Evans (1882-1971), anatomist and embryologist (bookplate).
FIRST EDITION, offprint issue, of Hubble's first paper on the discovery of what is now known as Hubble's Law: the proportionality of distance and radial velocity of galaxies, indicating an expanding universe. "Though only six pages in length, Hubble's first paper on the velocity-distance relation represented a giant step in modern cosmology... In place of a static picture of the cosmos, it seemed to many that the universe must be regarded as expanding, the rate of the mutual recession of its parts increasing with their relative distance" (Christianson). Hubble's discovery "made as great a change in man's conception of the universe as the Copernican revolution 400 years before" (DSB). Christianson Edwin Hubble: Mariner of the Nebulae pp.188-92).
HUBBLE, Edwin. "The Nature of the Nebulae." Offprint from: The Smithsonian Report for 1938. Pages 137-148. Washington, D.C.: Smithsonian Institution, 1939. 8o (243 x 154 mm). One plate. Original buff printed wrappers, uncut. Public lecture delivered in San Francisco 21 March 1938 on the occasion of the presentation of the Bruce Gold Medal of the Astronomical Society of the Pacific. Reprinted from The Publications of the Astronomical Society of the Pacific. Volume 50, No. 293, April 1938.
HUBBLE, Edwin. "The Problem of the Expanding Universe." Offprint from: The Smithsonian Report for 1942. Pages 119-132. Washington, D.C.: : Smithsonian Institution, 1943. 8o (244 x 153 mm). Original buff printed wrappers, uncut. Reprinted from the Sigma Xi quarterly. Volume 30, No. 2, April 1942. (3)