Niagara Falls Suspension Bridge
Encyclopedia
The Niagara Falls Suspension Bridge was the world's first working railway suspension bridge
Suspension bridge
A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. Outside Tibet and Bhutan, where the first examples of this type of bridge were built in the 15th century, this type of bridge dates from the early 19th century...

. It spanned 825 feet (251.5 m) and stood 2.5 miles (4 km) downstream of Niagara Falls
Niagara Falls
The Niagara Falls, located on the Niagara River draining Lake Erie into Lake Ontario, is the collective name for the Horseshoe Falls and the adjacent American Falls along with the comparatively small Bridal Veil Falls, which combined form the highest flow rate of any waterfalls in the world and has...

 from 1855 to 1897. Connecting Niagara Falls, Ontario
Niagara Falls, Ontario
Niagara Falls is a Canadian city on the Niagara River in the Golden Horseshoe region of Southern Ontario. The municipality was incorporated on June 12, 1903...

 to Niagara Falls, New York
Niagara Falls, New York
Niagara Falls is a city in Niagara County, New York, United States. As of the 2010 census, the city had a total population of 50,193, down from the 55,593 recorded in the 2000 census. It is across the Niagara River from Niagara Falls, Ontario , both named after the famed Niagara Falls which they...

 (the two cities assimilated the towns at the ends of the bridge by 1892), the bridge carried mixed traffic on its two decks across the Niagara River
Niagara River
The Niagara River flows north from Lake Erie to Lake Ontario. It forms part of the border between the Province of Ontario in Canada and New York State in the United States. There are differing theories as to the origin of the name of the river...

; trains crossed over the river by way of the bridge's upper deck while pedestrians and carriages used the lower. As the bridge was the result of a collaboration of two companies from two countries, it was also known by its American name, the International Suspension Bridge. The bridge had other names including the Niagara Railway Suspension Bridge and Niagara Suspension Bridge, but the most common and definitive was simply the Suspension Bridge.

The Suspension Bridge was part of Canadian politician William Hamilton Merritt
William Hamilton Merritt
William Hamilton Merritt was an influential figure in the Niagara Peninsula of Upper Canada in early 19th century and one of the fathers of the Welland Canal....

's vision to promote trade within his country and with its neighbor the United States. When Merritt and company invited the engineering community to bid for the bridge project, they encountered heavy criticism. Many bridge builders, and the general public, did not believe a suspension bridge could allow the safe passage of trains. Nonetheless, the bridge companies engaged several well-known civil engineers to build and maintain the bridge. Charles Ellet, Jr.
Charles Ellet, Jr.
Charles Ellet, Jr. was a civil engineer and a colonel during the American Civil War, mortally wounded at the Battle of Memphis.-Biography:Ellet was born in Bucks County, Pennsylvania, brother of Alfred W...

 was first hired to construct the bridge. Using a line laid by a kite
Kite
A kite is a tethered aircraft. The necessary lift that makes the kite wing fly is generated when air flows over and under the kite's wing, producing low pressure above the wing and high pressure below it. This deflection also generates horizontal drag along the direction of the wind...

 across the 800 feet (243.8 m) chasm, he built a temporary suspension bridge in 1848 as the first part of his plan. Not long after, Ellet left the project after a bitter financial dispute with the bridge companies. A three-year hiatus followed before the companies hired John Augustus Roebling
John A. Roebling
John Augustus Roebling was a German-born American civil engineer. He is famous for his wire rope suspension bridge designs, in particular, the design of the Brooklyn Bridge.-Early life:...

 to complete the project. Roebling used Ellet's bridge as scaffolding to build the double-decked bridge. By 1854 his bridge was nearly complete, and the lower deck was opened for pedestrian and carriage travel. On March 18, 1855, a fully laden passenger train drove across the upper deck at 5 miles per hour (8 km/h), and officially opened the completed bridge.

As a border crossing between Canada and the United States, the Suspension Bridge played significant roles in the histories of the Niagara region and the two countries. Three railway lines crossed over the bridge, connecting cities on both sides of the border. The Great Western Railway
Great Western Railway (Ontario)
The Great Western Railway was a historic Canadian railway that operated in Canada West and later the province of Ontario, following Confederation...

, New York Central Railroad
New York Central Railroad
The New York Central Railroad , known simply as the New York Central in its publicity, was a railroad operating in the Northeastern United States...

, and New York and Erie Rail Road
Erie Railroad
The Erie Railroad was a railroad that operated in New York State, New Jersey, Pennsylvania, Ohio, Indiana, and Illinois, originally connecting New York City with Lake Erie...

 differed in the width
Rail gauge
Track gauge or rail gauge is the distance between the inner sides of the heads of the two load bearing rails that make up a single railway line. Sixty percent of the world's railways use a standard gauge of . Wider gauges are called broad gauge; smaller gauges, narrow gauge. Break-of-gauge refers...

 of their tracks
Rail tracks
The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast , plus the underlying subgrade...

; the bridge used a triple gauge system to conserve space, overlapping two tracks on top of each other and using a rail of each to form the third track. The railroads brought a large influx of trade and tourists into the region around the Niagara Falls. Growing quickly from the traffic, the small towns at the ends of the bridge were integrated into the Niagara Falls cities. Many tourists flocked to the bridge to view the acclaimed marvel of engineering, as well as tightrope-walking daredevils who performed against the backdrop of the falls. In the time leading to the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

, the Underground Railroad
Underground Railroad
The Underground Railroad was an informal network of secret routes and safe houses used by 19th-century black slaves in the United States to escape to free states and Canada with the aid of abolitionists and allies who were sympathetic to their cause. The term is also applied to the abolitionists,...

 helped slaves in the United States escape across the Suspension Bridge to freedom in Canada. After the war, the bridge became a symbol of inspiration to Americans, encouraging them to rebuild their country and pushing them to quickly industrialize their nation.

Throughout its years of service, the Suspension Bridge stood strong and allowed thousands of passengers and trains to pass over it safely. Its success proved that, contrary to general opinion, a safe and operational railway suspension bridge was tenable, and allayed concerns induced by the 1854 collapse of the Wheeling Suspension Bridge
Wheeling Suspension Bridge
The Wheeling Suspension Bridge is a suspension bridge spanning the main channel of the Ohio River at Wheeling, West Virginia. It was the largest suspension bridge in the world from 1849 until the Queenston-Lewiston Bridge was opened in 1851. It was designed by Charles Ellet Jr., who also worked...

. Slowly decaying, the bridge's wooden structures were replaced with steel and iron versions by 1886, and the renovated bridge was stronger, capable of bearing a heavier load. By the end of the 19th century, the weight of trains had increased greatly and far exceeded the maximum capacity of the bridge. The Suspension Bridge was finally replaced by the Steel Arch Bridge, which was later renamed the Whirlpool Rapids Bridge
Whirlpool Rapids Bridge
The Whirlpool Rapids Bridge, commonly called the Whirlpool Bridge, and until 1937, known as the Lower Steel Arch Bridge, is a spandrel braced, riveted, two-hinged arch bridge. It crosses the international border between Canada and the United States, connecting the commercial downtown districts of...

, on August 27, 1897. When the Suspension Bridge was dismantled, its wire cables were found not to have noticeably degraded, a testament to its strength and design.

Conception and building

In the middle of the 19th century, the hinterlands of the North American East Coast were opened up rapidly; colonists moved further inland, pushing back the wilderness and establishing settlements that grew into towns and cities. The growth of these centers of civilization was fueled by the increasing number of routes set up to facilitate trade
Trade route
A trade route is a logistical network identified as a series of pathways and stoppages used for the commercial transport of cargo. Allowing goods to reach distant markets, a single trade route contains long distance arteries which may further be connected to several smaller networks of commercial...

 among the settlements. Canadian entrepreneur and politician William Hamilton Merritt
William Hamilton Merritt
William Hamilton Merritt was an influential figure in the Niagara Peninsula of Upper Canada in early 19th century and one of the fathers of the Welland Canal....

 was a major contributor to the establishment of several trade routes in his country. His primary focus was on the lakes and the dredging of waterways to open up trade between the lake cities. He also showed interest in railroads, envisioning a network that connected cities on both sides of the United States–Canadian border from the Atlantic coast in the East to the new territories in the West. Merritt's dream would lead to the creation of a man-made structure, a railway suspension bridge
Suspension bridge
A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. Outside Tibet and Bhutan, where the first examples of this type of bridge were built in the 15th century, this type of bridge dates from the early 19th century...

, that spanned the Niagara River
Niagara River
The Niagara River flows north from Lake Erie to Lake Ontario. It forms part of the border between the Province of Ontario in Canada and New York State in the United States. There are differing theories as to the origin of the name of the river...

 alongside the river's acclaimed natural feature, the Niagara Falls
Niagara Falls
The Niagara Falls, located on the Niagara River draining Lake Erie into Lake Ontario, is the collective name for the Horseshoe Falls and the adjacent American Falls along with the comparatively small Bridal Veil Falls, which combined form the highest flow rate of any waterfalls in the world and has...

.

Merritt's vision for the Niagara Suspension Bridge was conceived at the Niagara River itself. In the summer of 1844 while taking a picnic on the river shores, near what was then the town of Clifton
Clifton Hill (Niagara Falls)
Clifton Hill is one of the major tourist promenades in Niagara Falls, Ontario. The street, close in proximity to Niagara Falls and the Niagara River, leads from River Road on the Niagara Parkway to intersect with Victoria Avenue. The street contains a number of gift shops, wax museums, haunted...

, Merritt read a letter from his sons to his wife. The younger Merritts were touring Europe and visited the town of Fribourg
Fribourg
Fribourg is the capital of the Swiss canton of Fribourg and the district of Sarine. It is located on both sides of the river Saane/Sarine, on the Swiss plateau, and is an important economic, administrative and educational center on the cultural border between German and French Switzerland...

, Switzerland. Amazed by the Freiburg Suspension Bridge, they wrote to their parents, describing the wonders of the bridge in eloquent terms. Their writing had a profound effect on their parents, and the elder Merritts wondered if such a suspension bridge could be built across the Niagara. Merritt was driven to realize that vision, and he approached the relevant authorities, including the Queen of England, for permission to start the construction of the suspension bridge. His efforts were rewarded in 1846; the state of New York and the government of Canada approved the charters to form the Niagara Falls International Bridge Company and the Niagara Falls Suspension Bridge Company, respectively.

In the years before the first bridge was built over the Niagara River, the river was crossed entirely by boats. Powered by steam engines, vessels ferried people and carriages across the raging river at calmer points of the water. One of these vessels was the Maid of the Mist
Maid of the Mist
The Maid of the Mist is a boat tour of Niagara Falls. The boat starts off at a calm part of the Niagara River, near the Rainbow Bridge, and takes its passengers past the American and Bridal Veil Falls, then into the dense mist of spray inside the curve of the Horseshoe...

, the first tourist boat to ply the waters of the Niagara River. Named after a local legend, the steamer began service in 1846. Launching from a point 2 miles (3.2 km) below the Horseshoe Falls
Horseshoe Falls
The Horseshoe Falls, also known as the Canadian Falls, is part of Niagara Falls, on the Niagara River. Approximately 90% of the Niagara River, after diversions for hydropower generation, flows over Horseshoe Falls. The remaining 10% flows over the American Falls...

, it chugged up to the base of the falls, offering a close-up view of the natural wonder to its passengers, before moving to the opposite shore. The site for the Suspension Bridge was half a mile (0.8 km) from the Maid of the Mists landings. The selection of the bridge site was based more on aesthetics than technical ease; it was the narrowest point of the gorge—800 feet (243.8 m) across and 230 feet (70.1 m) deep—that allowed a full view of the falls from the American side.

After the bridge companies were founded, they invited engineers to submit plans and cost estimates for a suspension bridge that carried a railway. The invitation was met with skepticism among the engineering community. At that time, there was not a suspension bridge that could allow a train to pass over it safely. While the Europeans were erecting suspension bridges by the hundreds, the Americans mostly ignored them out of safety concerns; in 1831 Sir Samuel Brown
Samuel Brown (Royal Navy officer)
Captain Sir Samuel Brown of Netherbyres KH FRSE was an early pioneer of chain design and manufacture and of suspension bridge design and construction. He is best known for the Union Bridge of 1820, the first vehicular suspension bridge in Britain.-Naval career:Brown was born in London, the son of...

's Broughton Suspension Bridge
Broughton Suspension Bridge
Broughton Suspension Bridge was a suspended-deck suspension bridge built in 1826 to span the River Irwell between Broughton and Pendleton, now in Greater Manchester, England. It was one of the first suspension bridges constructed in Europe. On 12 April 1831 the bridge collapsed, reportedly owing...

 in Britain had collapsed under the marching feet of a troop of soldiers, sending those on its deck into the River Irwell
River Irwell
The River Irwell is a long river which flows through the Irwell Valley in the counties of Lancashire and Greater Manchester in North West England. The river's source is at Irwell Springs on Deerplay Moor, approximately north of Bacup, in the parish of Cliviger, Lancashire...

. Furthermore, many American bridges had collapsed without experiencing weight and pressure equivalent to railroad traffic, and American engineers feared that any railway bridge would likely fail—especially a suspension bridge.

Four engineers responded: Edward Serrell, Samuel Keefer, Charles Ellet, Jr.
Charles Ellet, Jr.
Charles Ellet, Jr. was a civil engineer and a colonel during the American Civil War, mortally wounded at the Battle of Memphis.-Biography:Ellet was born in Bucks County, Pennsylvania, brother of Alfred W...

, and John Augustus Roebling
John A. Roebling
John Augustus Roebling was a German-born American civil engineer. He is famous for his wire rope suspension bridge designs, in particular, the design of the Brooklyn Bridge.-Early life:...

. All submitted designs for a suspension bridge. At the time of the bidding, Ellet and Roebling were acknowledged as masters of suspension bridge building in America. Roebling submitted two designs, a conservative single-deck suspension bridge and a double-decked version, both with meticulous calculations and drawings. Instead of relying solely on submissions, Charles Ellet, Jr. took a proactive approach. When he got wind of the project in 1845, he wrote to Charles B. Stuart
Charles B. Stuart
Charles Beebe Stuart was an American engineer, United States Navy and Union Army officer and politician.-Biography:...

, chief engineer of the Great Western Railway
Great Western Railway (Ontario)
The Great Western Railway was a historic Canadian railway that operated in Canada West and later the province of Ontario, following Confederation...

, boldly proclaiming that he could build a bridge for any likely purpose across the Niagara. After the charters had been obtained, Ellet helped Stuart to sell the bridge companies' stock and offered to buy US$
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....

30,000 worth of stock himself. His efforts earned him the $190,000 bridge contract on November 9, 1847.

Charles Ellet, Jr.'s temporary bridge

While growing up on a farm in Pennsylvania, Charles Ellet, Jr. scraped through odd jobs, but saved enough money to finance an education at the École nationale des Ponts et Chaussées
École Nationale des Ponts et Chaussées
Founded in 1747, the École nationale des ponts et chaussées , often referred to as les Ponts, is the world's oldest civil engineering school...

 in France. After attending four months of lectures, he toured Europe before returning to the United States as the only native-born American with European education in engineering. Ellet announced his ambitions to build suspension bridges in his country of birth by proposing to span the Potomac River
Potomac River
The Potomac River flows into the Chesapeake Bay, located along the mid-Atlantic coast of the United States. The river is approximately long, with a drainage area of about 14,700 square miles...

 with one. His proposal was ignored; few were willing to heed a young, inexperienced and impetuous engineer. To gain experience, Ellet started to work on railroads and canals, and later became the chief engineer on the James River and Kanawha Canal
James River and Kanawha Canal
The James River and Kanawha Canal was a canal in Virginia, which was built to facilitate shipments of passengers and freight by water between the western counties of Virginia and the coast....

 project. He further improved his reputation by contributing articles about suspension bridges to respected engineering journals, such as American Railroad Journal; eventually, Ellet built his first suspension bridge over the Schuylkill River
Schuylkill River
The Schuylkill River is a river in Pennsylvania. It is a designated Pennsylvania Scenic River.The river is about long. Its watershed of about lies entirely within the state of Pennsylvania. The source of its eastern branch is in the Appalachian Mountains at Tuscarora Springs, near Tamaqua in...

, Pennsylvania, in 1842.

Ellet had the looks of an actor, which were complemented by his entertaining oratorical skills. He took advantage of these characteristics, and used showmanship and dramatics to market his proposals. These skills helped to win him attention and raise his profile both in the public and within the industry. However, his imperiousness also ruffled the feathers of people, which caused conflicts. Nonetheless, his capability to promote himself had won him the contracts for the Suspension Bridge and the later Wheeling Suspension Bridge
Wheeling Suspension Bridge
The Wheeling Suspension Bridge is a suspension bridge spanning the main channel of the Ohio River at Wheeling, West Virginia. It was the largest suspension bridge in the world from 1849 until the Queenston-Lewiston Bridge was opened in 1851. It was designed by Charles Ellet Jr., who also worked...

; the Wheeling contract was won in July 1847 while Ellet's plan for the Niagara Suspension Bridge was still in its initial stages of construction. Ellet's initial design for the bridge at Niagara placed all forms of transportation on a single deck. The railway track
Rail tracks
The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast , plus the underlying subgrade...

 was in the middle of the deck, sandwiched between carriageways and footpaths on the outer sides. Moreover, trains would not go over the bridge; their cars would be disconnected from the heavy locomotives and pulled across the bridge by horses, cables, or lighter 6 short tons (5.4 t) engines. Before the work could begin, Ellet faced the problem of all suspension bridge construction: getting a line across the gap.

Ellet's brainstorming sessions with his men raised several ideas that could enable a line to be suspended across the gorge; these included firing cannon balls with the line attached, towing it across the river with a steamer, and tying it to a rocket that would then be launched across the gorge. Ultimately the bridge engineer chose an idea inspired by Benjamin Franklin
Benjamin Franklin
Dr. Benjamin Franklin was one of the Founding Fathers of the United States. A noted polymath, Franklin was a leading author, printer, political theorist, politician, postmaster, scientist, musician, inventor, satirist, civic activist, statesman, and diplomat...

's experiment with a kite
Kite
A kite is a tethered aircraft. The necessary lift that makes the kite wing fly is generated when air flows over and under the kite's wing, producing low pressure above the wing and high pressure below it. This deflection also generates horizontal drag along the direction of the wind...

. It was similar to 15th century inventor Leonardo da Vinci
Leonardo da Vinci
Leonardo di ser Piero da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance...

's plan to span a gap. Ellet also took the opportunity to generate publicity for his project. Organizing a kite-flying contest, he offered $5 to any boy who flew a kite across the gorge and secured the kite string to the other side. Youths from nearby towns flocked in to participate. Unlike the other boys who flew their kites from the United States side of the gorge, 16-year-old Homan Walsh crossed the river by a ferry upstream and walked to the Canadian side of the bridge site to launch his kite. He almost succeeded on his first attempt; his kite flew across but crashed just short of the shore. After resting several days at a friend's house, Walsh finally got his kite across the gorge and secured its line to a tree.

Charles Ellet and his team tied a heavier line to the kite string and pulled the joined lines across. They pulled successive heavier and stronger lines across until the final bridge cable—7/8 in thick—was hanging across the gorge. The cable was suspended between two wooden towers 40 feet (12.2 m) feet tall, and it was attached to an iron basket. Ellet planned to use this system as a basket ferry to shuttle workers and materials across the gorge, saving time that would otherwise have been spent on land and ferry travel. Through media coverage and word-of-mouth, many people knew of Ellet's efforts and flocked to the site to watch the construction. On March 13, 1848, the system was completed, and the team planned to test it by pulling the empty basket across. They hit a snag when the basket kept getting stuck halfway and could not move ahead. Pulling back the basket, Ellet decided to assure the watching crowd that the system was workable. He stepped into the basket, and it moved towards the opposite shore. When Ellet reached the problematic spot, he spotted the issue; the basket's rollers could not pass over a portion of the cable that had been accidentally flattened during the construction. He fixed the problem and proceeded to cross to the Canadian side and back, becoming the first person to cross the gorge. Although the bridge companies had prohibited Ellet from collecting tolls, he charged each person $1.00 for the chance to "observe first hand the engineering wonder of bridging the Niagara". On some days, the basket ferry conveyed up to 125 people across the gorge.

Continuing his construction, Ellet built two footbridges and joined them together to form an 8 feet (2.4 m) wide suspension bridge. He intended to use this temporary bridge as a scaffold for the construction of the permanent railway bridge. On July 29, 1848, the bridge builder inaugurated the span in his typical manner; standing in his horse-buggy like a gladiator
Gladiator
A gladiator was an armed combatant who entertained audiences in the Roman Republic and Roman Empire in violent confrontations with other gladiators, wild animals, and condemned criminals. Some gladiators were volunteers who risked their legal and social standing and their lives by appearing in the...

 in his chariot, Ellet sped across the bridge, which had railings for only a third of its length at that time. His stunt garnered further publicity for the bridge, and the toll collected from the span proved lucrative; $5,000 was collected in less than a year since its official opening on August 1, 1848. Disputes arose between the bridge companies and Ellet over their shares of the money, and their relations turned bitter. The companies charged that Ellet was late in his schedule and withheld payment. Ellet retaliated by mounting cannons at the bridge to claim ownership over it. In the end the matter went to court. The bridge companies paid $10,000 to Charles Ellet, and he left the project to work full-time on the Wheeling Suspension Bridge.

The Niagara Suspension Bridge project was in hiatus for three years before the bridge companies engaged another renowned civil engineer, John Augustus Roebling, to complete it. The delay caused Roebling to miss out on the honor of building the first permanent bridge to span the Niagara; Serrell completed the Lewiston Suspension bridge in 1851. Roebling would, however, achieve other honors in building his Niagara Railway Suspension Bridge.

John Augustus Roebling's railway bridge

Born in Prussia
Prussia
Prussia was a German kingdom and historic state originating out of the Duchy of Prussia and the Margraviate of Brandenburg. For centuries, the House of Hohenzollern ruled Prussia, successfully expanding its size by way of an unusually well-organized and effective army. Prussia shaped the history...

 (later a part of Germany), John Augustus Roebling obtained his first conditional engineering degree (Feldmesserprüfung) at Erfurt
Erfurt
Erfurt is the capital city of Thuringia and the main city nearest to the geographical centre of Germany, located 100 km SW of Leipzig, 150 km N of Nuremberg and 180 km SE of Hannover. Erfurt Airport can be reached by plane via Munich. It lies in the southern part of the Thuringian...

 in 1824. He attended two semesters of lessons at Berlin's Bauakademie
Bauakademie
The Bauakademie in Berlin, Germany, built between 1832 and 1836, is considered one of the forerunners of modern architecture due to its theretofore uncommon use of red brick and the relatively streamlined facade of the building.Designed by Karl Friedrich Schinkel, the Bauakademie was built near...

 and worked for the Prussian government, constructing military roads. Tired of the bureaucracy, he resigned his position and left for the United States in 1830, arriving with his brother in Philadelphia on August 6, 1831. Instead of continuing an engineering profession, he took up farming for a living. After five years he married a tailor's daughter, and had eight children with her over the next decade. Agrarian work was unsatisfactory to John Roebling, and in 1837, after the death of his brother and the birth of his first child, he returned to engineering.

Roebling first signed on as a surveyor for the Beaver River canal system, launching his career with a string of canal and railroad projects. Aside from writing articles in engineering journals, Roebling designed his own wire cables and started his own company to manufacture them; the John A. Roebling Company was the first wire rope
Wire rope
thumb|Steel wire rope Wire rope is a type of rope which consists of several strands of metal wire laid into a helix. Initially wrought iron wires were used, but today steel is the main material used for wire ropes....

 manufacturer in the United States. Gradually gaining fame for his civil engineering, Roebling finally got to build suspension bridges. His first bridge was the Allegheny Suspension Aqueduct in Pittsburgh. The structure, completed in 1845, was the first suspension aqueduct in the world and the first large American suspension bridge that had multiple spans. Furthermore, it was the first suspension structure built with modern cable spinning techniques—Roebling's own invention. Earlier bridge building techniques involved fabricating the main cables at a factory, transporting them to the bridge site, and then stretching the heavy cables over the gap to erect them over the bridge. Roebling, during his experiments with wire ropes, conceived and patented a new construction method for these main cables. A long line—the traveler rope—formed a loop around two horizontal wheels, one on each side of the gorge. A lightweight wheel, "the traveling wheel", was attached to this line, and a wire threaded around this wheel. Like a belt
Belt (mechanical)
A belt is a loop of flexible material used to link two or more rotating shafts mechanically. Belts may be used as a source of motion, to transmit power efficiently, or to track relative movement. Belts are looped over pulleys. In a two pulley system, the belt can either drive the pulleys in the...

 in a mechanical system, the traveler rope and its wheel moved across the gap as the horizontal wheels turned, pulling the wire along. The traveling wheel effectively hauled two lengths of the same wire (running above and under the traveling wheel) across the gap at a time. The lengths of wire were collected and bound at intervals to form thicker strands, which were later compressed together into the main cables. which supported themselves and later the proportional weight of the bridge as they were formed. The method became the standard for suspension bridge construction, and remained unchanged for many years. In the 20th century, suspension bridges were still built with this pulley winding system, albeit with more sophisticated equipment.

John Roebling was a contrasting character to Charles Ellet. Whereas Ellet embellished his proposals with fanciful words and deeds, Roebling presented papers filled with meticulous calculations and drawings. The elder engineer was stern and driven to achieve, taking a scientific approach to all interests. Rarely did he show emotions in his dealings, even to his closest associates. The man, however, dared to confront his detractors and make bold exaltations about his work. He openly called European suspension bridges—including American suspension bridges built with European techniques—weak, and occasionally sniped at Ellet's and Stephenson's works. He announced that his Brooklyn Bridge
Brooklyn Bridge
The Brooklyn Bridge is one of the oldest suspension bridges in the United States. Completed in 1883, it connects the New York City boroughs of Manhattan and Brooklyn by spanning the East River...

, when completed, "will not only be the greatest bridge in existence, but it will be the greatest engineering work of this continent, and of the age." Roebling's history with Ellet started before the bidding for the Niagara Suspension Bridge, early in their careers. During the bidding for the Schuylkill Suspension Bridge project, Ellet had written a proposal that was published in the American Railroad Journal. Mistakenly believing Ellet had won the contract, Roebling wrote to offer his congratulations and requested to be Ellet's assistant. He received a formal reply without any reference to his request, and his subsequent letter was ignored. When Roebling learned that a contractor had won the bid, he successfully applied to be the contractor's chief engineer. Ellet, however, persisted with his tactics and snatched the project away from the contractor; he promoted himself to the bridge company and offered to accept land
Lot (real estate)
In real estate, a lot or plot is a tract or parcel of land owned or meant to be owned by some owner. A lot is essentially considered a parcel of real property in some countries or immovable property in other countries...

 instead of cash as payment. From then on, Ellet and Roebling became rivals, vying with each other for suspension bridge projects in North America. Roebling learned from their rivalry. His losses to Ellet showed him that he needed to promote himself and gain backers to effectively secure the contracts he desired.

When Roebling was called to the Niagara Suspension Bridge project in 1851, he had six suspension structures to his name. He found Ellet's final plan to be impractical; the bridge would have been too heavy and expensive. Roebling had another design in mind: the double-deck bridge he had proposed earlier during the bidding. The lower deck, level with the edge of the chasm, would convey passengers and carriages, and the upper deck, 18 feet (5.5 m) above, would allow fully laden trains to continue their journeys non-stop, albeit at a speed of 5 miles per hour (8 km/h). Roebling reasoned that the decks and sufficient truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...

es would form a rigid tube, making the bridge stiffer than a normal suspension bridge. The theory was similar to that of the tubular bridge
Tubular bridge
A tubular bridge is a bridge built as a rigid box girder section within which the traffic is carried. Famous examples include the original Britannia Bridge over the Menai Strait and the Conwy railway bridge over the River Conwy, designed and tested by William Fairbairn and built by Robert...

 but implemented at a lower cost. The engineering community was critical of Roebling's project. Robert Stephenson
Robert Stephenson
Robert Stephenson FRS was an English civil engineer. He was the only son of George Stephenson, the famed locomotive builder and railway engineer; many of the achievements popularly credited to his father were actually the joint efforts of father and son.-Early life :He was born on the 16th of...

, builder of the tubular Britannia Bridge
Britannia Bridge
Britannia Bridge is a bridge across the Menai Strait between the island of Anglesey and the mainland of Wales. It was originally designed and built by Robert Stephenson as a tubular bridge of wrought iron rectangular box-section spans for carrying rail traffic...

, was among those short-listed to complete the Niagara Suspension Bridge before Roebling's selection. Stephenson had submitted a design for a tubular bridge, and in 1859 he built a large and expensive tubular bridge for the Grand Trunk Railway
Grand Trunk Railway
The Grand Trunk Railway was a railway system which operated in the Canadian provinces of Quebec and Ontario, as well as the American states of Connecticut, Maine, Michigan, Massachusetts, New Hampshire, and Vermont. The railway was operated from headquarters in Montreal, Quebec; however, corporate...

 at Montreal, Quebec. The bridge builder then said in derision of Roebling's suspension railway, "If your bridge succeeds, mine is a magnificent blunder."

In the face of criticism, Roebling completed the project in four years, using Ellet's bridge as scaffolding. The railway deck was stress-tested by the crossing of the 23 short tons (20.9 t) steam engine London at a speed of 8 miles per hour (12.9 km/h) on March 8, 1855. Ten days later the upper deck of the bridge was officially opened; the lower deck had been opened to the public a year earlier. As the first commercial passenger train trundled over the bridge, the two countries were finally connected by railroad across the Niagara River. The successful crossings of these and later trains made Roebling's Suspension Bridge the first working suspension railway bridge in history.

Engineering

Roebling's bridge was supported by two limestone towers on each side of the gorge. These Egyptian-style
Ancient Egyptian architecture
The Nile valley has been the site of one of the most influential civilizations which developed a vast array of diverse structures encompassing ancient Egyptian architecture...

 towers stood 88 feet (26.8 m) tall on the American shore and 78 feet (23.8 m) tall on the Canadian shore. With their foundations 28 feet (8.5 m) in the earth, the limestone structures could support up to 12 million pounds (5.4 million kg). Four 10.5 inches (26.7 cm) thick main cables held up the bridge; two cables ran through iron saddles at the top of each tower. Each cable comprised 3,059 wires that were spun with Roebling's patented technique used in his Allegheny Suspension Aqueduct. The ends of each cable were secured to 6 square foot (0.55741824 m²) cast-iron plates sunk 20–30 ft (6.1–9.1 m) deep in the bedrock. Support lines hung down from iron clamps that encircled the main cables, and held up the decks. Deep trusses—never before seen on a large suspension bridge—lined the sides of the bridge, and joined the two decks so that the structure looked like a cage.< The trussed sides and the upper and lower decks, which spanned 825 feet (251.5 m), formed a "hollow straight beam", reinforcing the rigidity of the bridge.

The Suspension Bridge was further stiffened by guy-wire
Guy-wire
A guy-wire or guy-rope, also known as simply a guy, is a tensioned cable designed to add stability to structures . One end of the cable is attached to the structure, and the other is anchored to the ground at a distance from the structure's base...

s which ran from its upper deck to the top of its towers. Criticism of suspension bridges was growing after the Wheeling Suspension Bridge collapsed under strong winds in 1854. To address these concerns, Roebling added more guy-wires to secure the lower deck to the shores below. Roebling's efforts ensured that his Suspension Bridge remained standing while other suspension bridges across the Niagara River collapsed because of strong winds. Although he was not the first engineer to appreciate the need for a suspension bridge to be sufficiently rigid or to implement the methods to do so, Roebling was the first to understand the principles behind the methods and combine them in the building of a suspension bridge. Roebling proved that despite popular opinion, properly built suspension bridges can safely support the passage of heavy railway traffic. The engineer's combination of stiffening methods created the first modern suspension bridge. Such was the rigidity of the Suspension Bridge that it withstood the shockwave caused by the nearby fall of a 5000 short tons (4,535.9 t) mass of rock in 1863; the force of the impact manifested itself as a wave, rippling through the decks of the bridge from the American side to the Canadian side and back.

From the United States, the New York and Erie Rail Road
Erie Railroad
The Erie Railroad was a railroad that operated in New York State, New Jersey, Pennsylvania, Ohio, Indiana, and Illinois, originally connecting New York City with Lake Erie...

's Canandaigua and Niagara Falls Railroad and New York Central Railroad
New York Central Railroad
The New York Central Railroad , known simply as the New York Central in its publicity, was a railroad operating in the Northeastern United States...

's Buffalo and Niagara Falls Railroad
Buffalo and Niagara Falls Railroad
The Buffalo and Niagara Falls Railroad was a part of the New York Central Railroad system, connecting Buffalo, New York to Niagara Falls. It is still used by CSX for freight and Amtrak for passenger service.-History:...

 crossed over the bridge and reached into Ontario. Similarly, the Great Western Railway in Canada extended its network from Canada into New York. At the time of the bridge's opening, the three railroads were of different gauges: on the New York Central, on the Great Western, and on the Erie. Instead of accommodating three railways side-by-side on a single wide deck, the bridge saved space by overlapping the tracks over each other. This method used only four rails; one pair formed the track for one railway, and the other pair formed another. One rail from each pair would then form the final track. In the first year of the bridge's operation, an average of 30 trains trundled across it each day. Five years later, 45 trains passed over the structure daily.

Roebling mandated that the trains be limited to a maximum speed of 5 miles per hour (8 km/h) to ensure absolute safety. He was confident the bridge could handle faster train traffic, but he preferred a safe operation. In his tests the bridge supported a 326 short tons (295.7 t) train, bending 10.5 inches (26.7 cm) under the weight. This was within the maximum load of 450 short tons (408.2 t) specified in the design of the bridge. The figure was a conservative estimate. The cables and guy-wires could support 7300 short tons (6,622.4 t), and travel journalist Alfred J. Pairpoint commented that it was normal to see 1200 short tons (1,088.6 t) trains pass over the bridge without danger. The bridge shook whenever a train trundled over it, although this had no effect on its integrity. When the frequency of passing trains was high, the trembling was noticeable to travelers on the lower deck and proved uncomfortable to some; writer Mark Twain
Mark Twain
Samuel Langhorne Clemens , better known by his pen name Mark Twain, was an American author and humorist...

 noted, "You drive over to Suspension Bridge and divide your misery between the chances of smashing down two hundred feet into the river below, and the chances of having a railway-train overhead smashing down onto you. Either possibility is discomforting taken by itself, but, mixed together, they amount in the aggregate to positive unhappiness." Despite such commentaries, thousands of people crossed over the bridge safely every day.

American engineers regard the Suspension Bridge as a major achievement of efficiency. In a fledgling country where resources—material and financial—were limited, they had to make do with whatever was available. This goal was espoused by the American Society of Civil Engineers
American Society of Civil Engineers
The American Society of Civil Engineers is a professional body founded in 1852 to represent members of the civil engineering profession worldwide. It is the oldest national engineering society in the United States. ASCE's vision is to have engineers positioned as global leaders who strive toward...

, which opined, "That is the best engineering, not which makes the most splendid, or even the most perfect work, but that which makes a work that answers the purpose well, at the least cost." Roebling had built a bridge that rivaled grander bridges of leading European nations at a much lower cost. His Suspension Bridge used only one-sixth the material of Stephenson's Brittania Bridge, but was twice as long and had a capacity that exceeded the tubular bridge. Moreover, the expenditure on Roebling's Suspension Bridge was $400,000, whereas a tubular bridge of equivalent length and load-bearing capability would have cost $4 million. Roebling's success established him as the master of suspension bridges. The inclined guy-wires that stretched from the top of towers to the roadway of the Suspension Bridge became the signature of his future works.

Although the Suspension Bridge proved that the suspension system could be safely used to carry railroads, no more suspension railway bridges were built. The outbreak of the American Civil War diverted attention from such civil engineering ventures, and by the time attention was paid to building bridges again, cantilever bridge
Cantilever bridge
A cantilever bridge is a bridge built using cantilevers, structures that project horizontally into space, supported on only one end. For small footbridges, the cantilevers may be simple beams; however, large cantilever bridges designed to handle road or rail traffic use trusses built from...

s were in vogue for railway bridges. Regardless, the Suspension Bridge's success made it a model for suspension railway bridges. When the city of Quebec called for a structure to span the St. Lawrence River in 1850, it looked to the Suspension Bridge for inspiration. Seventeen years later, the British journal Engineering called for a suspension railway to bridge the Straits of Messina and also referred to Roebling's bridge. Lastly, Stuart opened his 1871 work on the history of American engineering, Lives and Works of Civil and Military Engineering in America, with an illustration of the bridge.

Legacy

As a border crossing between two large growing countries, the Suspension Bridge had throngs of travelers passing over it. Furthermore, it was the intersection of three major railroads. Coupled with its vicinity to a natural wonder, the Niagara Falls, the bridge brought a lot of railroad traffic into the region once it was opened. The towns at the ends of the bridge benefited greatly from this heavy movement of people and goods. The village of Suspension Bridge, United States, grew quickly within a few years after the opening of the bridge, acquiring shops, factories, and a hotel. Its tourism and commerce soon rivaled the town of Niagara Falls, New York
Niagara Falls, New York
Niagara Falls is a city in Niagara County, New York, United States. As of the 2010 census, the city had a total population of 50,193, down from the 55,593 recorded in the 2000 census. It is across the Niagara River from Niagara Falls, Ontario , both named after the famed Niagara Falls which they...

; eventually, the village was merged into the town in 1892. Similarly, Clifton on the Canadian end of the bridge was integrated into the town of Niagara Falls, Ontario
Niagara Falls, Ontario
Niagara Falls is a Canadian city on the Niagara River in the Golden Horseshoe region of Southern Ontario. The municipality was incorporated on June 12, 1903...

. The two Niagara Falls cities boasted commerce that surpassed neighboring settlements. Around the time of its official opening, the bridge was one of the busiest points of trade on the United States–Canadian border, carrying $12 million of transitory goods and $2 million of bonded materials into Canada. To handle the large amount of goods exchanged over the border, the Lewiston customs house—the primary customs for the Niagara region—was relocated to the Niagara Suspension Bridge in 1863.

The bridge's depiction as an engineering marvel and beautiful sight lured many visitors to the Falls. Travelers could, while crossing the bridge, enjoy a view of the Falls enhanced by the sensation of standing 250 feet (76.2 m) in the air. The Falls, however, proved distant and indistinct to some when there was overcast weather. On the whole, the Suspension Bridge was considered as an attraction that must be seen by visitors to Niagara Falls.< In paintings and prints of the bridge, the Suspension Bridge became the focus, pushing the Falls into the background. Unlike paintings of the Falls that capture the viewer's eye with their majestic views of the natural wonder, pictures of the bridge impressed viewers with the utilitarian design of the structure. By 1897, the inbound trains to Niagara Falls brought 276,900 visitors during the months of May to August. A streetcar system
Tram
A tram is a passenger rail vehicle which runs on tracks along public urban streets and also sometimes on separate rights of way. It may also run between cities and/or towns , and/or partially grade separated even in the cities...

 was established in 1882 to handle the increasing cross-border pedestrian traffic. Initially pulled by horses, the trolleys were converted to run on electricity in 1892. The Suspension Bridge was the pride and symbol of the Great Western Railway, which touted it as the "only Route via Niagara Falls & Suspension Bridge".

Travelers on the Suspension Bridge witnessed several death-defying stunts performed across the Niagara Gorge. On June 30, 1859, they saw Charles Blondin
Charles Blondin
Jean François Gravelet-Blondin was a French tightrope walker and acrobat.-Life:Blondin was born on 24 February 1824 at St Omer, Pas-de-Calais, France. His real name was Jean-François Gravelet, and he was known also by the names Charles Blondin or Jean-François Blondin, or more simply "The Great...

's feat of becoming the first man to cross the chasm on a tightrope. In mid-crossing Blondin sat down on the rope and lowered a line to retrieve a drink from the deck of the Maid of the Mist below. In his later tightrope acts at the same spot, the acrobat would perform a different stunt on each occasion. One time he cooked and ate an omelette in mid-crossing; another time he carried his manager Harry Colcord on his back. While giving Colcord a piggyback ride, Blondin stopped five times on the tightrope to rest and recover his strength; each time Colcord gingerly got off Blondin's back and stood on the tightrope, climbing back on after the acrobat had enough rest. Blondin's success inspired other acrobats, such as William Leonard Hunt
William Leonard Hunt
William Leonard Hunt , also known by the stage name The Great Farini, was a well known nineteenth and early twentieth century Canadian funambulist, entertainment promoter and inventor, as well as the first known white man to cross the Kalahari Desert on foot and survive.-Early life:Hunt, the second...

 ("The Great Farini"), Samuel Dixon, Clifford Calverly, and Signorina Maria Spelterini
Maria Spelterini
Maria Spelterini , born , was an Italian tightrope walker who was the only woman to cross the Niagara gorge on a tightrope, which she did on July 8, 1876. She used two and a quarter inch wire and crossed just north of the lower suspension bridge...

, to emulate and try to surpass his acts at the same spot. The Signorina, the only woman to walk across the Niagara on a tightrope, once crossed while blindfolded and another time with her hands and legs in manacles.

Another group of people in America had their own risky crossings over the Niagara Gorge as they fled over the border into Canada. They were enslaved African-Americans who sought freedom by escaping to a country that declared the liberation of any slave who entered it. The bridge was part of the Underground Railroad
Underground Railroad
The Underground Railroad was an informal network of secret routes and safe houses used by 19th-century black slaves in the United States to escape to free states and Canada with the aid of abolitionists and allies who were sympathetic to their cause. The term is also applied to the abolitionists,...

, a network of routes designed to smuggle slaves in the United States to freedom in Canada. Before the American Civil War, fleeing slaves had only four main routes into Canada, of which one was crossing the Niagara River. Slaves who escaped along the Niagara route had help from several quarters. The state of New York generally favored granting freedom to slaves; this attitude emboldened African-American workers in Niagara, who frequently helped slaves flee to Canada. Before the Suspension Bridge was completed, fugitives either crossed the raging river on a boat or risked their lives by swimming at calmer points of the river. The Suspension Bridge made escape across the river easier and safer, although there was still risk. To avoid getting caught and sent back to their owners, slaves had to sneak across on foot or hide aboard trains and oxcarts. Antislavery activist Harriet Tubman
Harriet Tubman
Harriet Tubman Harriet Tubman Harriet Tubman (born Araminta Harriet Ross; (1820 – 1913) was an African-American abolitionist, humanitarian, and Union spy during the American Civil War. After escaping from slavery, into which she was born, she made thirteen missions to rescue more than 70 slaves...

 guided fugitives at night and bribed custom officials to turn a blind eye. As a result, many slaves crossed the Suspension Bridge to freedom before the United States was engulfed in civil war.

When the war ended and the United States turned its focus toward rebuilding, Roebling started building his Brooklyn Bridge
Brooklyn Bridge
The Brooklyn Bridge is one of the oldest suspension bridges in the United States. Completed in 1883, it connects the New York City boroughs of Manhattan and Brooklyn by spanning the East River...

. As the monumental task could affect naval navigation, it required state approval, and the government wanted a thorough review of the engineer's credentials; hence, a Bridge Party was organized. Comprising Roebling and his son, as well as their fellow bridge engineers, generals, businessmen, and high society figures, the party toured the country to review four bridges Roebling had built before the civil war. The final item on their itinerary was Roebling's Niagara Suspension Bridge. At the dinner to commemorate the end of the bridge tour, civil war veteran General Henry Warner Slocum
Henry Warner Slocum
Henry Warner Slocum , was a Union general during the American Civil War and later served in the United States House of Representatives from New York. During the war, he was one of the youngest major generals in the Army and fought numerous major battles in the Eastern Theater and in Georgia and the...

 gave a toast and called the Suspension Bridge a symbol of inspiration for the United States in its rebuilding efforts. This sentiment was shared by the guests and was expressed at later dinners across the United States. The achievement of building a large suspension bridge over a gorge in the face of overwhelming adversity—constant put-downs by the professional community, American and European—gave the United States a sense of pride. Nationalism rose as the country lauded the bridge. The completion of the bridge that had been deemed impossible by the Western world gave Americans, who had lesser technical accomplishments than Europe at that time, a trophy that stood above any other. The Suspension Bridge became the American symbol to brave the toughest of challenges and do the impossible, pushing their drive for industrialization even harder. Charles W. Woodman
Charles W. Woodman
Charles Walhart Woodman was a U.S. Representative from Illinois.Woodman was born in Aalborg, Denmark and was educated in the schools of his native country. In 1863 Woodman emigrated to the United States arriving in Philadelphia and immediately enlisted in the Gulf Squadron of the United States Navy...

 specifically drew attention to the Suspension Bridge in his 1865 address to the United States Senate for approval to build a rail system to transport a ship
Patent slip
The patent slip or Marine Railway was invented by Scot Thomas Morton in 1818 as a cheaper alternative to a dry dock for ship repair. It consisted of an inclined plane, which extended well into the water, and a wooden cradle onto which a ship was floated...

 out of the water and up around the Niagara Falls.

Maintenance and replacement

Budget concerns forced Roebling to build the Suspension Bridge primarily with wood; the cost of casting the components out of iron and transporting them "[way] out West" was exorbitant. The organic material decayed and rotted because of the moisture present around Niagara Falls. As the industrialization of the United States moved forward rapidly, the introduction of the Bessemer process
Bessemer process
The Bessemer process was the first inexpensive industrial process for the mass-production of steel from molten pig iron. The process is named after its inventor, Henry Bessemer, who took out a patent on the process in 1855. The process was independently discovered in 1851 by William Kelly...

 greatly lowered the cost of the more durable steel and iron. By 1880, the Suspension Bridge's wooden trusses, beams, and flooring were replaced with steel. The wire cables were not replaced; their cores were still in pristine condition. The outer layer of wires in the cables was, however, lightly corroded and had to be replaced. Due to severe deterioration, the limestone towers were replaced in 1886 with steel framed versions. These renovations increased the bridge's strength and helped it handle heavier loads for a few more years.

The weight of trains in North America had greatly increased by the mid-1890s. Larger and more powerful locomotives were required to pull cars that handled an increasing number of passengers and goods; compared to the 23 short tons (20.9 t) locomotives crossing the bridge in the 1850s, 170 short tons (154.2 t) locomotives were the common engines 40 years later. The weight of these trains exceeded the specifications of the Suspension Bridge, and the bridge companies took the opportunity to review and request the replacement of the bridge. Civil engineer Leffert L. Buck
Leffert L. Buck
Leffert L. Buck was an American civil engineer and a pioneer in the use of steel arch bridge structures. Leffert graduated from Rensselaer Polytechnic Institute in Troy, NY in 1868...

, who had been hired to maintain the Suspension Bridge, was selected to design the replacement bridge. He settled for a bridge of the arch design
Arch bridge
An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side...

. At that time, arch bridges were the new models for railway bridges and were more cost-efficient than suspension bridges. Buck built the new bridge around and below the Suspension Bridge, replacing it a piece at a time. His plan allowed bridge traffic—train and pedestrian—to continue without disruption. By August 27, 1897, the last pieces of the Suspension Bridge were dismantled, leaving the Lower Steel Arch Bridge—later renamed the Whirlpool Rapids Bridge
Whirlpool Rapids Bridge
The Whirlpool Rapids Bridge, commonly called the Whirlpool Bridge, and until 1937, known as the Lower Steel Arch Bridge, is a spandrel braced, riveted, two-hinged arch bridge. It crosses the international border between Canada and the United States, connecting the commercial downtown districts of...

—in its stead. On inspection, the cores of the cables that formerly held up the Suspension Bridge were found to be as sound as on the day the bridge was built.

External links

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