The Ashuelot Covered Bridge is located at the center of Ashuelot, NH. It is a Town lattice truss bridge, spanning the Ashuelot River in a roughly north-south orientation. It consists of two spans with a total length of 178 feet (54 m). The total width of the bridge is 29 feet (8.8 m), and has a central roadway and sidewalks (measuring 3'10" in width) on each side. The bridge rests on stone abutments and a central pier. The abutments have been reinforced with concrete since the bridge was built, and the central pier has been protected by a metal breakwater.
1860-1869
In the context of naval warfare, H.L. Hunley changed the world. Its builders' innovative use of materials, design and manufacturing techniques resulted in the world's first successful attack submarine.
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Image Credit: Edwin GrosvenorEra_date_from: 1860
2007
Most great monuments of nineteenth-century American engineering, such as the Brooklyn Bridge, dominate the surrounding landscape. By contrast, the Hoosac Tunnel, dug through a mountain in western Massachusetts, is inconspicuous, as tunnels naturally are. Yet it stands in the front rank of the projects of its age by whatever standards of measurement one chooses. On the one hand, its construction, which began in 1851 and ended in 1875, took almost two hundred lives, damaged many reputations, and nearly claimed the solvency of the commonwealth of Massachusetts.
The discoveries of electricity in the latter half of the 18th Century, and its close connection with magnetism, were the products of earlier experiments, which in turn led to the invention of the electric telegraph. Telegraphy had connected the interior of the United States, and it also connected Europe together. However, connecting the Americas and Europe proved to be a challenge. Due to the electric current that ran through the cable lines, insulation and waterproofing was necessary.
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Image Credit: Courtesy IEEEImage Caption: The County Kerry Cable StationsEra_date_from: 1866
2000
"May God continue the unity of our Country as this Railroad unites the two great Oceans of the world."
- Inscription on the ceremonial Golden Spike
The symbolic Golden Spike, staked in Promontory, Utah in 1869, marked the completion of the first transcontinental railroad, joining the Union Pacific Railroad from the East and the Central Pacific Railroad from the west.
Constructed to provide a safe, potable water supply for the citizens of Chicago, Ellis Chesbrough's Chicago Water Supply System was the first major system to utilize offshore intake systems. The system includes the landmark Chicago Water Tower and the Chicago Avenue Pumping Station. Its subaqueous tunnel was a pioneering effort in American civil engineering.
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Image Credit: Courtesy Wikipedia/WickdrewImage Caption: Ellis Chesbrough's Chicago Water Supply System was the first major system to utilize offshore intake systems.Era_date_from: 1864
1972
The Watkins Woolen Mill is among the best preserved examples of a Midwest woolen mill in nineteenth-century United States. Its machinery for preparing, spinning, and weaving wool reflects the existence of well-established textile industry in the country. It was designed and built by Waltus L. Watkins (1806-1884), a machinist and master weaver from Frankfort, Kentucky, who began operating his mill in 1861 in Clay County.
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Image Credit: Public Domain (National Park Service)Image Caption: Watkins Woolen MillEra_date_from: 1868
1980
The Cairo is the sole survivor of the fleet of river gunboats built by the Union during the Civil War with the object of controlling the lower Mississippi River. Designed by Samuel Pook and built by James B. Eads, it saw limited battle and was sunk on the Yazoo River in 1862 by newly developed electronically detonated mines, becoming the first craft ever sunk by this predecessor to torpedo technology. The 175-foot ironclad vessel had 13 guns.
The design of the Bollman Truss Bridge-patented in 1852 and one of the first to use iron exclusively in all essential structural elements-was critical in the rapid expansion of American railroads in the 19th century. Replacing wooden bridges, which were cumbersome to build and vulnerable to decay, the Bollman Truss Bridge could be built relatively quickly and inexpensively, while providing the long-lasting qualities associated with metal. This allowed new rail lines to be built over long distances in a short period of time.
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Image Credit: Courtesy Flickr/Andrew Bossi (CC BY-SA 2.0)Image Caption: Bollman Truss Bridge as it looks today, after the repairs done in 1934-84.Era_date_from: 1869
1966
Central Pacific Railroad served as the Western terminus of America's first transcontinental railroad, passing through the formidable Sierra Nevada Mountains. In all, 15 tunnels were blasted through solid granite.
Thousands of Chinese from Kwantung Province were recruited by Central Pacific Railroad Company and became known for their diligence and hard work. In the second year of construction, nine out of ten workers on the CPRR were Chinese.
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Image Credit: Courtesy Flickr/Jim Bowen (CC BY 2.0)Image Caption: Central Pacific RailroadEra_date_from: 1863
1968
Innovations
Bread is considered a basic foodstuff; eaten down through the ages, it continues to be a staple of the modern diet. The development of baking powder made baking easier, quicker and more reliable for bakers in the mid-19th century. Eben Horsford’s unique formula was an important innovation and…
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People thought inventor Walter Aiken was crazy when he proposed a railway to the top of Mt. Washington. Aiken built a model of the roadbed and track with a cog rail system, but entrepreneur Sylvester Marsh is credited for launching the Cog Railway and bringing Aiken's ideas to fruition.
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A product of the Northern California Gold Rush, the Bridgeport Covered Bridge is believed to be the longest, single-span, wooden covered bridge in the United States. Crossing the south fork of the Yuba River at a span of 233 feet, the bridge was built by the Virginia City Turnpike Company as…
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Cabin John Aqueduct, designed by Montgomery C. Meigs, conveys drinking water from Great Falls, Maryland to Washington, D.C. It was the longest stone masonry arch in the world for nearly 40 years. The segmental arch of the bridge has a span of 220 feet and a rise of only 57 feet. The main arch…
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The William H. Chandler Chemistry Laboratory was conceived and planned by William Henry Chandler (1841-1906), professor, chairman, librarian, and acting president of Lehigh University. Designed by Philadelphia architect Addison Hutton and erected between 1884 and 1885 at a cost of $200,000, the…
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These engines, built by Cooper & Co., of Mount Vernon are among the oldest surviving agricultural steam engines to show the evolution from the portable, skid-mounted engine (ca. 1860) to the horse-drawn engine (1875), through the self-propelled but horse-guided engine (1875) and finally to…
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The Cornish-Windsor Covered Bridge is the longest wooden bridge in the United States and the longest two-span, covered bridge in the world. It is also a classic example of wooden bridge-building in 19th-century America. With copious supplies of timber at hand and a generous reserve of carpentry…
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In 1866, the Covington and Cincinnati Suspension Bridge was the largest suspension bridge in the world. Also called the Ohio Bridge, it was officially renamed the John A. Roebling Bridge in 1983. It was the first permanent bridge over the Ohio River and the only public project in America…
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The La Esperanza sugar mill steam engine is one of the few remaining American links to the pioneer beam engines of the English inventors Thomas Newcomen (1712) and James Watt (1769). The engine was built in 1861 in Cold Spring, New York, by the West Point Foundry. The general arrangement and…
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Minot's Ledge is a wave-swept rock formation in a rocky area of ocean about a mile off the Cohasset shore near Boston. Numerous serious shipwrecks prompted the government to erect a beacon there, and construction began in the summer of 1847.
The light, constructed on tall iron legs…
Just 20 years after settling the uninhabited Salt Lake valley, Brigham Young and his Mormon followers completed one of the nation's most impressive public structures. The 9,000-seat Mormon Tabernacle boasts a clear span roof measuring 150 feet by 250 feet, its timber trusses joined with wooden…
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Designed, patented, and built by Thomas W.H. Moseley, this arched 96-foot span bridge preceded by years the standard use of wrought iron for bridges. For the first time in the United States, Moseley incorporated the use of riveted wrought-iron plates for the triangular-shaped top chord.
…
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The Mullan Road was designed to facilitate the movement of troops and supplies across the Rocky Mountains between the Missouri River basin in the Great Plains and the Columbia River Basin at the Columbia Plateau during times of Indian hostilities. But because peace was reached with the Northwest…
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The idea of creating a canal linking the Mediterranean Sea to the Red Sea is a very old one that dates back about 4000 years to the ancient Egyptians. They thought of linking the two seas by using the River Nile and its branches. It was this very old desire that led to the digging of the present…
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Central Pacific Railroad served as the Western terminus of America's first transcontinental railroad, passing through the formidable Sierra Nevada Mountains. In all, 15 tunnels were blasted through solid granite.
Thousands of Chinese from Kwantung Province were recruited by Central…
Read More
The design of the Bollman Truss Bridge-patented in 1852 and one of the first to use iron exclusively in all essential structural elements-was critical in the rapid expansion of American railroads in the 19th century. Replacing wooden bridges, which were cumbersome to build and vulnerable to…
Read More
The Cairo is the sole survivor of the fleet of river gunboats built by the Union during the Civil War with the object of controlling the lower Mississippi River. Designed by Samuel Pook and built by James B. Eads, it saw limited battle and was sunk on the Yazoo River in 1862 by newly developed…
Read More
The Watkins Woolen Mill is among the best preserved examples of a Midwest woolen mill in nineteenth-century United States. Its machinery for preparing, spinning, and weaving wool reflects the existence of well-established textile industry in the country. It was designed and built by Waltus L.…
Read More
Constructed to provide a safe, potable water supply for the citizens of Chicago, Ellis Chesbrough's Chicago Water Supply System was the first major system to utilize offshore intake systems. The system includes the landmark Chicago Water Tower and the Chicago Avenue Pumping Station. Its…
Read More
"May God continue the unity of our Country as this Railroad unites the two great Oceans of the world."
- Inscription on the ceremonial Golden Spike
The symbolic Golden Spike, staked in Promontory, Utah in 1869, marked the completion of the first transcontinental railroad,…
Read More