(WORLD WAR II - D-DAY). NINE ENGINEERING DRAWINGS AND PLANS RELATING TO "OPERATION MULBERRY," BY I. IORYS HUGHES

Together 9 large sheets of draughtsman's tracing paper (from approximately 24 1/4 x 10 1/4 in.; 616 x 260 mm, to 38 x 23 1/4 in.; 965 x 591 mm), signed (“I. Iorys Hughes”), and dated variously between 17 June and 6 August 1942. Lot includes: No. 1: “General Layout Sketch of Reinforced concrete Jetties to be Sunk in Place.”  One sheet (25 1/2  x 11 1/4 in.; 648 x 286 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 19 June 1942, annotated diagrams of port operation from sea to beach with troop positions, mechanized assault vehicles, tides, bridges and pontoons, along with side and top views. No. 2: “Reinforced Concrete Jetties — Typical Pontoon to be Sunk in Place.”  One sheet (24 1/4 x 17 1/2 in.; 616 x 445 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 17 June 1942, annotated diagrams of half shear, half longitudinal, half deck, half section, and transverse sectional views. No. 3: “Leader Pontoon — to be Sunk in Place.”  One sheet (24 3/4 x 17 in.; 629 x 432 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 17 June 1942, one drafting page, annotated diagrams of half shear, half longitudinal, half deck, half section and transverse sectional views. No. 4: “Reinforced Concrete Jetties, Details of Steel Bridges.” One page (24 3/4 x 13 1/4 in.; 629 x 337 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer]”; June 20, 1942, one drafting page, annotated diagrams of three types of bridges: “A”, “B”, and “C”, with sketch of “Putting Bridges in Place.” No. 5: “Reinforced Concrete Jetties, Lay-Out of Yard.” One sheet (24 1/4 x 10 1/4 in.; 616 x 260 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 20 June 1942, annotated diagrams of composite plan and cross section; concrete mold composition. With “Establishment Cost... £12,500” and “Plant, Hire, Fuel, etc £45 per. week”. No. 6: “Proposed Landing Jetty, General Details, Slung Span and Cantilever Type.” One sheet (38 x 23 1/4 in.; 965 x 591 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 6 August 1942, annotated diagrams of “twistable slung span,” decking, and concrete frame and hull, with detailed cutaways of key sections. No. 7: “Proposed Landing Jetty, Lay-Out Plan, Slung Span and Cantilever Type.” One sheet (35 1/2 x 13 3/4 in.; 902 x 349 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 6 August 1942, annotated diagrams of side elevation, including pontoons joined by slung span and cantilever superstructures, and composite plan with notation of tidal direction. No. 8: “Proposed Landing Jetty, Notes on Erection, Slung Span Type.” One sheet (19 1/2 x 9 1/2 in.; 495 x 241 mm), annotated diagram of “Launching of Slung Span," with written instructions for its assembly and operation. No. 9: “Top Plan, Longitudinal Section, and Side Elevation.” One sheet (35 1/2 x 19 in.; 902 x 483 mm), signed “I. Iorys Hughes, M[echanical] Eng[ineer],” 6 August 1942, annotated diagrams with enlarged view of span in place and midspan section. Extremely detailed dimensional and construction directions.

The secret wartime plans for the prototypes of the celebrated Mulberry Harbors, which played an enormous part in the success of the landings at Normandy After the evacuation at Dunkirk in 1940, the Nazis believed that a counter-invasion of France was impossible without the capture of a port to handle the supplies necessary to support ground troops.  Prime minister Winston S. Churchill and his War Office decided to overcome this problem by building a mobile port which the troops could take with them.  I. Iorys Hughes, who had worked on such peacetime projects as Wembley Stadium and the Hyde Park underpass, was thought to be the perfect candidate for this complex task.

The present set of plans, dating between 17 June and 6 August 1942, are those which were prepared and retained by Hughes himself.  One or more further sets would have gone to the War Office, where they and additional plans were developed by their team.  Following this, in an operation codenamed "Mulberry," officially described as "one of the best kept secrets of World War II," the massive harbors themselves were built in early 1943 and May 1944. They were successfully launched with the use of tugboats, and the operation was fully justified by the events of 6 June 1944, when the harbors were used at Arromanches and Omaha Beach.