Lot 29
PRATT H. B., Commercial Airships. London: Nelson 1920, 8vo, 235pp, Original blue cloth with gilt lettered spine, fading to spine and cover, rubbing to corners and edges of spine. Endpaper with dedication "With the author's compliment H B Pratt 11/11/20", endpaper also signed B.N. Wallis. Sir Barnes Wallis and H B Pratt worked together as young engineers on the R9 airship in 1914  £200-300