Sidelights on Relativity

First English language edition, first printing.[4], 56, [4], 8pp, with occasional small illustrations in text.  Blue cloth-covered boards with black lettering and rules on upper panel, black lettering to spine.  Printed on heavy  stock paper. Slim 12mo.  Cloth is a little worn, faded around edges and over spine, gently rubbed on edges in places and on corners and spine ends.  Upper text block edge dust darkened, remaining edges very slightly toned.  Some spotting and browning on first and last few pages, lightly so throughout. Previous owner's name neatly inked on front paste down; three instances of inked marginal notes on pp 13, 18 and 19.   Neat, clean and tightly bound. First English language edition of Einstein's Spotlights on Relativity (following Relativity: The Special & the General Theory - A Popular Exposition, 1920), containing two of his addresses relating to the theory of relativity: (i)  Ether and Relativity and (ii) Geometry and Experience.