Original U.S. Patent Document, March 10, 1908, No. 881,327. Eight pages, 8x11.5", stapled left margin, two full-page illustrations and three pages of specifications. The invention is for a bagless, gasless airship with a vertical propeller below the gondola for lift and a horizontal propeller for forward motion. Montgomery is a well-known inventor, engineer and professor who experimented with gliders near San Diego in the 1880's and is considered a prominent figure in early flight history. Very good condition; one horizontal fold, prominent aviation collector rubber stamp on first blank page.