New York, June 2, 1913. 3 pp. 11 x 8 1/2 in. (279 x 215 mm). Typed letter, signed by Hoover ("H C Hoover"), as a consulting engineering expert, to mining magnate and philanthropist, Adolph Lewisohn; additional lengthy MS. postscript by Hoover on p. 3. "Received" ink stamp, dated Jun 3-1913, at top right corner of each page. On Hoover's personal stationery; creasing from original folds; hole punch in top left corner of each page, staple holes along top edge. Together with: (London), September 2, 1913. 1 p. 10 1/4 x 8 1/4 in. (260 x 209 mm). Typed letter, signed by Hoover ("H C Hoover"), to Messrs. Adolph Lewisohn & Sons. On Hoover's personal stationery; faint "Received" ink stamp at top right, dated September 10, 1913; creasing from original folds. Lot includes a postcard portrait of Hoover.