Chicago River Bascule Bridge, Kinzie Street, Spanning North Branch Chi...
Significance: This single-leaf bascule bridge represents the transition between the early Chicago-type bascule bridge, first employed in the West Cortland Street Bridge (see HAER No. IL-138), and subsequent imp... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Outer Drive, Spanning Chicago River at O...
Significance: At the time of its completion in 1937, the Outer Drive Bridge was the longest and widest bascule bridge in the world. Survey number: HAER IL-54 Building/structure dates: 1929 Initial Constructio... More
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Columbus Avenue, Spanning Chicago River ...
Public domain photograph - historical image of Illinois, United States, free to use, no copyright restrictions image - Picryl description
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Franklin Street, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Clarke Street, Spanning Chicago River at...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Clarke Street, Spanning Chicago River at...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Franklin Street, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Outer Drive, Spanning Chicago River at O...
Significance: At the time of its completion in 1937, the Outer Drive Bridge was the longest and widest bascule bridge in the world. Survey number: HAER IL-54 Building/structure dates: 1929 Initial Constructio... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, Jackson Boulevard, Chicago, Cook County,...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Outer Drive, Spanning Chicago River at O...
Significance: At the time of its completion in 1937, the Outer Drive Bridge was the longest and widest bascule bridge in the world. Survey number: HAER IL-54 Building/structure dates: 1929 Initial Constructio... More
Chicago River Bascule Bridge, Clarke Street, Spanning Chicago River at...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Jackson Boulevard, Chicago, Cook County,...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Franklin Street, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Columbus Avenue, Spanning Chicago River ...
Public domain image of Chicago city buildings, cityscape, free to use, no copyright restrictions image - Picryl description
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, State Street, Spanning Chicago River at ...
Significance: Providing for eight lanes of traffic, the State Street Bridge contains three lines of trusses, part of which serve as a railing for the roadway and sidewalks. The railing-truss height was first u... More
Chicago River Bascule Bridge, Clarke Street, Spanning Chicago River at...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Jackson Boulevard, Chicago, Cook County,...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wells Street, Spanning South Branch Chic...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, Clarke Street, Spanning Chicago River at...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Columbus Avenue, Spanning Chicago River ...
Public domain photograph of stairs, steps, free to use, no copyright restrictions image - Picryl description
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Kinzie Street, Spanning North Branch Chi...
Significance: This single-leaf bascule bridge represents the transition between the early Chicago-type bascule bridge, first employed in the West Cortland Street Bridge (see HAER No. IL-138), and subsequent imp... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Kinzie Street, Spanning North Branch Chi...
Significance: This single-leaf bascule bridge represents the transition between the early Chicago-type bascule bridge, first employed in the West Cortland Street Bridge (see HAER No. IL-138), and subsequent imp... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wells Street, Spanning South Branch Chic...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, Jackson Boulevard, Chicago, Cook County,...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Columbus Avenue, Spanning Chicago River ...
Public domain photograph - historical image of Illinois, United States, free to use, no copyright restrictions image - Picryl description
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Outer Drive, Spanning Chicago River at O...
Significance: At the time of its completion in 1937, the Outer Drive Bridge was the longest and widest bascule bridge in the world. Survey number: HAER IL-54 Building/structure dates: 1929 Initial Constructio... More
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, Jackson Boulevard, Chicago, Cook County,...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Franklin Street, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Franklin Street, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Canal Street, Spanning South Branch Chic...
Significance: Chicago city engineers employed their standard bascule design for this bridge carrying Canal Street Bridge across the South Branch of the Chicago River. Its streamlined bridgetender's house refle... More
Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of ...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Kinzie Street, Spanning North Branch Chi...
Significance: This single-leaf bascule bridge represents the transition between the early Chicago-type bascule bridge, first employed in the West Cortland Street Bridge (see HAER No. IL-138), and subsequent imp... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Wells Street, Spanning South Branch Chic...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, State Street, Spanning Chicago River at ...
Significance: Providing for eight lanes of traffic, the State Street Bridge contains three lines of trusses, part of which serve as a railing for the roadway and sidewalks. The railing-truss height was first u... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Wabash Avenue, Spanning Chicago River at...
Significance: In 1930 the Wabash Bridge was awarded the American Institute of Steel Construction prize for "Most Beautiful." Survey number: HAER IL-48 Building/structure dates: 1930 Initial Construction
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Columbus Avenue, Spanning Chicago River ...
Public domain photograph - historical image of Illinois, United States, free to use, no copyright restrictions image - Picryl description
Chicago River Bascule Bridge, Michigan Avenue, Spanning Chicago River ...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River a...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, Jackson Boulevard, Chicago, Cook County,...
Significance: The development of the Chicago trunnion bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Chicago River Bascule Bridge, Outer Drive, Spanning Chicago River at O...
Significance: At the time of its completion in 1937, the Outer Drive Bridge was the longest and widest bascule bridge in the world. Survey number: HAER IL-54 Building/structure dates: 1929 Initial Constructio... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More
Chicago River Bascule Bridge, Washington Street, Spanning Chicago Rive...
Public domain photograph of construction site, free to use, no copyright restrictions image - Picryl description
Chicago River Bascule Bridge, Grand Avenue, Spanning North Branch Chic...
Significance: The Grand Avenue Bridge represents the "second generation" of the Chicago bascule bridge with improvements executed in the design of the counterweights, a new rack-and-pinion assembly (namely, the... More
Chicago River Bascule Bridge, West Cortland Street, Spanning North Bra...
Significance: Designated a landmark by the American Society of Civil Engineers, the Cortland Street Bridge is a double-leaf bascule span that became in the early twentieth century the standard for movable bridg... More