THOMAS A. EDISON Fine content illustrated A.L.S. "E", 1p. oblong 8vo., [n.p., 1920] to Jaffrey P. Buchanan, manager of Edison's Record Disc Division, in dark pencil as was Edison's custom. Edison illustrates his plan to prevent powder used in the production of phonograph discs from billowing about the screw-type feeder and otherwise being wasted. He writes in full: "Buchanan - Want to call your attention in connection with devices for saving powder in blank dept. Thet the greater distance powder of any kind drops, the more dust is carried into the air. E." Edison then draws two simple illustrations, the first showing the present situation with the powder dropping loosely onto the screw-type feeder and blowing about the machinery (labeled "Bad dust" ), with the second drawing showing a side view of ramps arranged vertically not unlike a child's beach toy allowing the powder to slide onto the feeder (labeled "Hardly any dust" ). Light, even toning and a tiny marginal chip or two, one barely touching his initial, a label affixed at upper-left, else very good.  $700-900