C.G. Spencer & sons illustrated catalog, 8x10", wrps, 16 pages. Wonderful advertisements for spherical balloons, the "Spencer" parachute, the "Salvus" parachute, balloon baskets and accessories, captive (kite) balloons and an engineering drawing (side view) of the "Spencer" airship. Good; one vertical cover fold and very small edge tears. A rare early catalog representing balloon and airship technology at the end of WWI.