There are three drawn details: end view, part side elevation, lateral bracing in horizontal plane. The towers are the two end parts of the bridge that hold the central span and the suspended car. The towers are referred to as North and South. The South Tower is nearer to Minnesota Point, the North Tower is on the "mainland." Drawing 167, Sheet M11.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
This is a general elevation drawing, plus end view of both towers. The suspended car transfer is in the center of the bridge drawing over the canal. Dimensions are included for the distance from the water to the bottom of the bridge span (135 feet) and the footings. The drawing shows small stone and gravel fill near and around the concrete footings at the base of each tower. The finials are shown in detail. Lake Avenue is shown from one tower to the other. Drawing H-5421A, U.S. Patent February 1903.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
This carbon copy of a Claude Turner document is an historical overview about the bridge re-design. It includes discussion of contracts, alternate design, and petitions. Also includes exhibits A, B, and C from interested parties communicating with the Duluth City Council.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The suspended car transfer was replaced in 1929 with the Aerial Lift Bridge span. The building at the left is the wholesale grocer Gowan Lenning Twohy.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
This post card was mailed in 1906, but the image is from an earlier year. In the 1890s commercial fishing on Lake Superior was feeding Duluth and the entire Midwest with major operators: A. Booth and Sons (whose sign is visible at the left), Lake Superior Fish Company, H. Christiansen and Sons.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The caption says The Aerial Bridge Span 393 feet 9 inches, 135 feet high from water line, cost $100,000 Duluth, Minn. A few more details that are not on this card are that the Aerial Bridge was completed in February, 1905. The Aerial Bridge transporter or gondola or transfer car roadway was 17 feet by 50 feet with sidewalks seven feet by 50 feet and the cabins were 30 feet long. This original bridge was modified with the lift span in 1929 and first operated March 19, 1930.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The post card caption says The Aerial Bridge, Span 393 feet 9 inches, 135 feet high from water line. Cost $100,000. This post card illustration is of a view from the waterfront. At the right is the South Breakwater Inner Light Tower. Houses on Minnesota Point are at the far right. Engineer C.A.P. Turner, of the Gillette-Herzog Manufacturing Company of Minneapolis, designed the Ferry Bridge with Suspended Car Transfer in February 1901, meeting federal specifications. Bids were opened March 25, 1901, but only one was received. The Duluth Canal Bridge Company was awarded the contract but abandoned the work. In February, 1904, the Modern Steel Structural Company of Waukesha, Wisconsin was issued a contract. Work began July 20, 1904.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The caption of this post card says Clear span, 400 feet; clear height, 136 feet; total height above water, 186 feet. This view shows the waterfront when it was warehouses and wharves, docks, railroad freight sheds and slips. This view is probably from Skyline boulevard which, at this time, would have been called Rogers' Boulevard. William Rogers was the first parks department commissioner. In December 1959 the Duluth City Council and Mayor E. Clifford Bork changed the name of Rogers parkway and Skyline Boulevard to Skyline Parkway.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The caption of this post card says The Aerial Bridge, Span 393 feet 9 inches, 135 feet high from water line. Cost $100,000. Entrance to Duluth-Superior Harbor. The white building at the left is the U.S. Army Corps of Engineers Building constructed in 1906.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The post card caption says The Aerial Bridge, Span 393 feet 9 inches, 135 feet high from water line. Cost $100,000. This post card illustration is of a view from the Duluth harbor with the U.S. Army Corps of Engineers Building at the left and the South Breakwater Inner Light Tower at the right. Houses on Minnesota Point are at the far right. Engineer C.A.P. Turner, of the Gillette-Herzog Manufacturing Company of Minneapolis, designed the Ferry Bridge with Suspended Car Transfer in February 1901, meeting federal specifications. Bids were opened March 25, 1901, but only one was received. The Duluth Canal Bridge Company was awarded the contract but abandoned the work. In February, 1904, the Modern Steel Structural Company of Waukesha, Wisconsin was issued a contract. Work began July 20, 1904. The aerial bridge transporter or gondola or transfer car roadway was 17 feet by 50 feet with sidewalks seven feet by 50 feet; the cabins were 30 feet long.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
In 1893, James J. Hill's Northern Steamship Company built 385-foot ocean style passenger steamers. In 1911, the peak year, 80,000 passengers traveled to Lake Superior. After 1920, the number of passenger cruise ships diminished with the advent of "motor-cars." Very few cruise ships were still in service after World War II. The Canadian steel steamer Huronic was constructed in Collingwood, Ontario, in 1902. She ran on the Northern Navigation Division of the Canadian Steamship Company, on cruise trips from Detroit to Duluth. In 1940, the Huronic was dismantled and made into a package freighter.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
This drawing identifies wind forces and their effects on the physical structure. Notes are included on this drawing for example: "Stresses in lower sections of tension diagonals equal or smaller than top sections, but same riveting to be used in detail." The drawing includes a key for live load, dead load, impact, wind at 150 pounds per linear foot, wind stress due to traveler, equivalent to live load. The drawing shows top and bottom laterals. Total weight of the carrier and car is given as 240,000 pounds. The scale is given as 20 feet equaling one inch. Drawing H5421, Sheet 3.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
Detailed drawing of four parts of the Aerial Bridge. The end view is a drawing of a tower; part side elevation is of half of the Aerial Bridge with the suspended car transfer. The third drawing is called Section A-A and depicts a tower without the cross structures drawn in. The last drawing is called Section B-B, which is a top down view of one of the towers resting on its footings. All of these drawings have dimensions. The part side elevation includes a very small drawing of the side of the gondola car. The end view includes the phrase "car approaches built by city." The finials are shown on three of the four drawings. Drawing H5421, Sheet 2.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
Ore boat leaving Duluth. Detroit Publishing Co. was a prolific post card publisher, especially in the U.S. Their cards were published from 1898 to 1933. Using a color process called Phostint, their cards were considered to be very artistic. The hobby of collecting post cards is called deltiology. The first post card was issued by the Austrian government, America's first postcards came out in 1873. Picture postcards were introduced later. The golden age of postcards was supposed to date from 1907 through the first World War.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
This photograph may have been shot from Seventh Street and about Lake Avenue. The bright narrow strip in the lower middle of the image is Lake Avenue leading to the Aerial Bridge. The rectangle and three dots parallel to the piers of the canal are the remnants of the Whitney rock crushing enterprise. The Whitney Brothers, of Superior, Wisconsin, had a sand and gravel processing business that was functioning in 1919. The concrete form that is still in the water was the dredging/crushing building. A tunnel ran from the building to the Point. There was a conveyor belt and railroad spur adjacent to the concrete building. Sand from the Apostle Islands and gravel from Grand Marais were carried to Duluth on a small vessel named Limit. The business also used a tug the William A. Whitney. The Limit was secured to the concrete building and the load of sand or gravel was unloaded into the steel hopper using a jaw-like clam shell, steam powered device. The belt conveyed the materials to shore and it dropped into a tunnel where trucks were ready. On Federal lake charts it is referred to as cribs. Telephone lines are in this photograph. In 1880, the first telephones were installed in Duluth by Walter Van Brunt for C. H. Graves and Company. In 1881, the Duluth Telephone Company was incorporated with $10,000 capital. In 1882, the first telephone directory was issued for 30 subscribers. In 1898, long distance lines between Duluth, Cloquet and Carlton were strung. In 1899, Duluth had 794 telephones. In 1900, the Zenith telephone Company (independent) started operations in competition with Duluth Telephone Company. The tower is the Central High School clock tower. The 1892 school has been the Central Administration Building for ISD 709 since the late 1970s.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
Whaleback is an unusual ship design with steel hulls (body of the vessel) and rounded decks (boat, hurricane, main -which is the lowest full-length deck in a ship's hull, and spar are all decks at different levels) which was introduced by the inventor Captain Alexander McDougall of Duluth in 1888. It was a very stable vessel. American Steel Barge Company, a New York corporation engaged in shipbuilding and transportation on the Great Lakes as well as on the Atlantic and Pacific coasts, purchased all of the patents for McDougalls whaleback vessels for $25,000. The only remaining whaleback is the Meteor, which is now a museum at Barker's Island in Superior, Wisconsin.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
139-D The caption of this post card says The unique Aerial Lift Bridge and Ship Canal Entrance to Duluth-Superior Harbor is an outstanding attraction of this popular summer vacation city. Total bridge load lifted is 900 tons. Only 55 seconds are required to lift the span 135 feet. The Harbor is second only to that of New York City in shipping tonnage and through it passes about 60 per cent of America's iron ore production, from the great iron ore ranges just north of Duluth. Another fact, not included in the caption is that John H. Darling (1847-1942), U.S. Engineer for Duluth-Superior Harbor, oversaw replacement of the original wooden canal piers with concrete piers in 1897. The piers have been maintained and repaired with a major remodeling/rehabilitation in 1985-1986.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
The caption for this post card says The famous Aerial Lift Bridge, at the entrance to the Duluth -Superior harbor, is the largest of its kind in the world. The 900-ton span, lifted by electrical energy stored in batteries, rises 120 feet in 50 seconds each time a boat approaches the harbor.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections
View of the lift span taken from the southeast corner of the U.S. Army Corps of Engineers building (1906). The canal's piers have walkways, and there are benches for visitors to linger to watch the ships enter and exit the harbor. The Aerial Lift Bridge is the largest tourist attraction in the state of Minnesota. The enclosed portion on the lift span is the operator's house or the power house of the bridge. On one side of the operator is Lake Superior and the other side is Superior Bay and the Duluth Harbor Basin. Leonard P. Green was the bridge operator for 36 years (died September 16, 1944). He was supervisor when the Aerial bridge was altered to become the lift bridge. In 1932, Mr. Green's seven operators worked in eight-hour shifts, two operators to a shift.
Contributing Institution:
University of Minnesota Duluth, Kathryn A. Martin Library, Northeast Minnesota Historical Collections