When opened in 1909, the Queensboro Bridge had the two longest steel cantilever spans in the world - 1,182 feet from Manhattan to Blackwell's Island and 984 feet from Blackwell's Island to Queens. These would remain the world's longest cantilever spans until the completion of the Quebec Bridge in 1917. The Queensboro Bridge has an overall length of 3,724.5 feet. It originally carried two elevated railway lines, two trolley lines, six carriage lanes and two pedestrian walkways.
1900-1909
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Image Credit:
Courtesy Flickr/reivax (CC BY-SA 2.0)
Image Caption:
Queensboro Bridge
Era_date_from:
1909
2009
Used to lift molten iron to molds where it was cast into pipe, jib cranes were the sole means of conveyance in the pit-casting process. When pit casting was replaced by centrifugal casting in the 1920s, many pits were filled and the cranes were used to produce cast iron fittings or general maintenance work. Only one jib crane remained at the American Cast Iron Pipe Company in recent years, and it was probably the last pit-cast jib crane to operate, which it did until it was given to the Sloss Furnace Museum in early 1986.
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Image Credit:
Courtesy ASME
Image Caption:
The crane as it is used today, in general service
Era_date_from:
1905
1977
This was the first successful machine for mechanizing the identification and price marking of retail merchandise. At a single stroke of the operating handle, the machine formed a tag from a roll of stock, imprinted it with price and other information, formed a wire staple, and stapled the tag to the merchandise. This means for dispensing with handmade and written tags amounted to a minor revolution in the then rapidly expanding retail industry.
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Image Credit:
Courtesy ASME
Image Caption:
Pin-Ticketing Machine
Era_date_from:
1902
1990
Philadelphia City Hall was the largest masonry load-bearing wall building in the world at the time of its completion in 1901, stood as the tallest occupied building in the United States until 1909, and still is the largest city hall in the United States. The building covers 14.26 acres, originally contained 634 rooms with over 1 million square feet of space, and with its tower and statue of William Penn rises a total of 548 feet above the ground. The construction of Philadelphia City Hall began in 1872 and was completed in 1901.
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Image Credit:
Courtesy Flickr/elPadawan (CC BY-SA 2.0)
Image Caption:
Philadelphia City Hall
Era_date_from:
1901
2005
Opened July 9, 1904, this lift lock is the highest of its type in the world, transferring boats between two water levels in a single 19.8 m (65 ft.) lift. Designed in place of conventional locks, which would have lengthed the time considerably to transverse a gradual drop, this lift lock was a unique solution made feasible. It operates on a balance principle. Each boat chamber is supported by a ram, 2.28 m (7.5 ft.) In diameter. These move up and down inside water-filled cylinders connected by a pipe.
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Image Credit:
Courtesy Flickr/Mac Armstrong (CC BY-SA 2.0)
Image Caption:
Peterborough Hydraulic Canal Lift Lock
Era_date_from:
1904
1999
No image dominates the Midwestern landscape like the monolithic grain elevator, whose present shape and construction owe much to grain company operator Frank Peavy and architect-builder Charles Haglin.
Wanting to improve on the flammability and cost of traditional wood-cribbed construction, Peavy speculated that reinforced concrete, in its infancy at the turn of the century, would outperform other materials. But critics feared that the elevator would collapse due to the vacuum created when grain was emptied from the air-tight structure.
YearAdded:
Image Credit:
Courtesy Wikipedia/Original Uploader was Elkman (CC BY-SA 3.0)
Image Caption:
Peavey-Haglin Concrete Grain Elevator
Era_date_from:
1900
1983
This is the oldest operating vessel with a diagonal, compound steam engine, with disc valve gear. Operating at a higher pressure than the oscillating-cylinder engines then used in lake steamers, this type of engine was more powerful and efficient, as well as smaller. The compound engine, built by Sulzer brothers of Winterthur, uses super-heated steam from the boilers in two stages-high and low pressure-before exhausting it into a condenser. The engine produces 650 horsepower, turning two paddle wheels.
YearAdded:
Image Credit:
Courtesy Wikicommons/Coronado1992 (CC BY-SA 3.0)
Image Caption:
Paddle Steamer Uri
Era_date_from:
1901
1998
In 1900, Moses Gomberg, Professor of Chemistry at the University of Michigan, confirmed the existence of a stable, trivalent organic free radical: triphenylmethyl. In so doing, he challenged the then prevailing belief that carbon could have only four chemical bonds. Gomberg’s discovery made a major contribution to theoretical organic chemistry and fostered a field of research that continues to grow and expand. Today, organic free radicals are widely used in plastics and rubber manufacture, as well as medicine, agriculture and biochemistry.
YearAdded:
Image Credit:
Public Domain (Copyright Exp.)
Image Caption:
Discovery of Organic Free Radicals by Moses Gomberg
Era_date_from:
1900
2000
For more than a century, scientists at Rockefeller University have enhanced our understanding of the molecular basis of life — specifically the relationship between the structure and function of nucleic acids and proteins. They showed that DNA transfers genetic information and that the sugars ribose and deoxyribose are the key building blocks of the nucleic acids RNA and DNA.
YearAdded:
Image Credit:
Courtesy Flickr/S Shepherd (CC BY 2.0)
Image Caption:
Nucleic Acid and Protein Chemistry Research at Rockefeller University
Era_date_from:
1901
2000
The Northern Pacific High Line Bridge No. 64, built between 1907 and 1908, has continued to perform yeoman service in the uninterrupted flow of the Nation's commerce. Nearly, 100 years after this bridge officially opened, it still carries 125-ton car unit coal trains, double stack container trains, lumber, and refined products at train speeds of 50 m.p.h.
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Image Credit:
Original Photo: Public Domain; Produced prior to 1/1/1923
Image Caption:
Northern Pacific High Line Bridge No 64
Era_date_from:
1908
2004
Innovations
Opened July 9, 1904, this lift lock is the highest of its type in the world, transferring boats between two water levels in a single 19.8 m (65 ft.) lift. Designed in place of conventional locks, which would have lengthed the time considerably to transverse a gradual drop, this lift lock was a…
Read More
Philadelphia City Hall was the largest masonry load-bearing wall building in the world at the time of its completion in 1901, stood as the tallest occupied building in the United States until 1909, and still is the largest city hall in the United States. The building covers 14.26 acres,…
Read More
This was the first successful machine for mechanizing the identification and price marking of retail merchandise. At a single stroke of the operating handle, the machine formed a tag from a roll of stock, imprinted it with price and other information, formed a wire staple, and stapled the tag to…
Read More
Used to lift molten iron to molds where it was cast into pipe, jib cranes were the sole means of conveyance in the pit-casting process. When pit casting was replaced by centrifugal casting in the 1920s, many pits were filled and the cranes were used to produce cast iron fittings or general…
Read More
When opened in 1909, the Queensboro Bridge had the two longest steel cantilever spans in the world - 1,182 feet from Manhattan to Blackwell's Island and 984 feet from Blackwell's Island to Queens. These would remain the world's longest cantilever spans until the completion of the Quebec Bridge…
Read More
"The Alexanderson radio alternator was a high-power, radio-frequency source which provided reliable transoceanic radiotelegraph communication during and after World War I. Ernst F.W. Alexanderson (1878-1975), a General Electric engineer, designed radio alternators with a frequency range to 100 kHz… Read More
Installed alongside an Epping Carpenter pump that was later scrapped, this water pump was built by Allis-Chalmers, which for many years had Edwin Reynolds as its chief engineer. Driven by a Corliss steam engine, these large city water pumps were installed in Jacksonville's water supply…
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The third bridge built on the same site to carry railroad tracks across the Susquehanna River just north of Harrisburg, Pennsylvania, the Rockville Stone Arch Bridge, at 3,820 feet long and 52 feet wide, is believed to be the longest and widest stone-arch railroad bridge in the world. A central…
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Located at the northern tip of Michigan where Lake Superior, Lake Michigan, and Lake Huron join together, the Sault Ste. Marie Hydroelectric Power Complex was built to harness the hydroelectric potential of the 20-foot falls at the headwaters of the St. Marys (sic) River, the sole outlet of…
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The Victoria Falls Bridge, completed in 1905, is a 152-meter span, steel-lattice, two-hinged arch bridge with a deck level 122 m above the Zambezi River. Conceived by Cecil Rhodes as a key link in his proposed Cape-to-Cairo railway, it is situated just downstream of the Victoria Falls in a site of… Read More
The steel dome stretches 200 feet in diameter and rises 100 feet at its top. To accommodate thermal expansion, the inverted bowl-shaped structure originally rested on rollers that sat on the flat tops of six-story columns
There was a time when Americans from the Eastern seaboard braved…
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Combining British financing, American engineering, and Canadian contracting, the White Pass and Yukon was the first major civil engineering project on the continent above the 60th degree of northern latitude. Completed in 27 months using only hand tools, black powder, and regional timber, the…
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When opened in 1903, the 1,600 foot long main span of the Williamsburg Bridge was the world's longest suspension span, surpassing the nearby Brooklyn Bridge by only 4.5 feet. The Williamsburg Bridge remained the world's longest suspension bridge span for 21 years until the opening of the Bear…
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The 1905 Wright Flyer III, built by Wilbur (1867-1912) and Orville (1871-1948) Wright, was the world's first airplane capable of sustained, maneuverable flight. Similar in design to their celebrated first airplane, this machine featured a stronger structure, a larger engine turning new "bent-end…
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In the 19th century, New York City was a burgeoning industrial and commercial metropolis - the largest city in the United States and second largest in the world. As the city's population increased, people began to call for construction of an underground railway. Many unusual engineering…
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A transportation tunnel under the Hudson River connecting Manhattan and New Jersey was first considered in the 1860s, fueled by New York City's rapidly growing congestion and the inadequacy of existing ferry service to population centers across the river. DeWitt Clinton Haskin, an engineer…
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In the years following the Civil War, the land west of the Mississippi River was being settled and the Pacific Northwest explored. There remained, however, a large portion of Montana, Idaho, and Washington that contained enormous quantities of timber and minerals, but was not accessible by rail…
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In 1902 and 1903 he requested some patents for the system. With the Telekine, Torres-Quevedo laid down modern wireless remote-control operation principles.
Torres Quevedo also made some important contributions to aeronautics, a field in which he carried out important research on dirigible… Read More
The first use of wireless telegraphy in the field occurred during the Anglo-Boer War (1899-1902). The British Army experimented with Marconi's system and the British Navy successfully used it for communication among naval vessels in Delagoa Bay, prompting further development of Marconi's…
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On 24 December 1906, the first radio broadcast for entertainment and music was transmitted from Brant Rock, Massachusetts to the general public. This pioneering broadcast was achieved after years of development work by Reginald Aubrey Fessenden (1866-1932) who built a complete system of wireless…
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