This 1940s color documentary advertisement about suspension bridges is produced by the American Bridge Division of U.S. Steel, American Steel & Wire Division. The camera pans up from a stream to show a suspension bridge high above (:25-:35). Shown are a stone bridge, bridge arches, and covered bridges (:36-:49). A drawbridge closes (1:55). Pittsburgh has many bridges (2:13-3:08). An animation shows suspension bridges can be anchored into the water (typical) or self-anchored to the road (3:09-3:39). The bridge crossing the Monongahela River is the typical construction, with tower piers and main cables of parallel wires draped over the towers and from cable bands at spaced intervals (3:40-4:10). The bridge spanning the Allegheny River is self-anchored with links and suspenders of forged steel I-bars (4:11-4:44). Men in hard hats carry preformed bridge strand cables to make the Paseo Suspension Bridge. The strands are pulled off giant reels and lifted by pulley to a man on the top of a girder. Filler strips keep the strands perfectly parallel to each other while sockets are locked. The wires are pulled to a predefined tension (4:45-7:43). A simply hydraulic compacting device squeezes the cable to its final size and shape. The cable is temporarily banded and marked to show where it is to be attached (7:44-8:03). Two bridge construction workers wear safety lines while they straddle banded cable high in the air. Another group works off a large moving scaffold hung from wooden rollers (8:04-8:35). A bridge suspender rope is swung to a worker. The sockets on the ends of the suspenders are fitted into their seats on the girders beneath the roadway and secured by bolts (8:36-9:00). The wire wrapping machine is shown in operation (9:06-9:22). Red protective paste is applied (9:28). Splicing two spools of wrapping wire is shown, followed by the wrapping machine (9:38-10:00). Diagrams with interjected pictures of the bridge parts and blueprints for the Delaware Memorial Bridge are shown (10:24-11:28). The construction of the steel towers are diagrammed. To build them required catwalks of cyclone chain-link fencing and wooden cleats to be built over the water (11:30-13:48). Workers on the catwalks work on the tramway system for the spinning cable wheels that move the cable to another location to be attached. Wheels with cowbells attached as warnings pass each other on the lines (13:49-16:00). Counterweights maintain the tension (16:08). Splicing is diagramed (16:23-16:40). The large cable reels are transported by truck and barges and hoisted up. Cranes load the reels (16:42-18:04). The cable continues to be moved by the wheels laying down the wires. Cable bands are applied and coated (18:17-19:33). An animation shows the trusses are built outward at the same time. The process is shown, including men on girders attaching the meeting ends and working on the diagonals and bolts (20:10-24:40). A wrapping machine covers the cable and a protective paste applied (24:42-25:23). The entire suspension bridge is panned (25:27-26:00). The finished Delaware Memorial Bridge with its toll booths and traffic are shown (26:25-27:08).

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This film is part of the Periscope Film LLC archive, one of the largest historic military, transportation, and aviation stock footage collections in the USA. Entirely film backed, this material is available for licensing in 24p HD, 2k and 4k. For more information visit http://www.PeriscopeFilm.com