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91-641: The Rankin Bridge was built on the site of the 1897 steel truss West Braddock Bridge , a narrow trolley bridge equipped with a wooden deck. Like similar road-rail bridges in the area, the West Braddock Bridge was poorly suited to automobile and truck traffic, a deficiency the new bridge rectified. The Rankin Bridge was first and foremost an automobile bridge, but it also accommodated streetcars with equal facility as it carried Pittsburgh Railways trolley route #55 Homestead - East Pittsburgh on both

182-516: A streetcar or trolley in the United States) is a type of urban rail transit consisting of either individual railcars or self-propelled multiple unit trains that run on tramway tracks on urban public streets; some include segments on segregated right-of-way . The tramlines or tram networks operated as public transport are called tramways or simply trams/streetcars. Because of their close similarities, trams are commonly included in

273-665: A third rail , but some use pantographs, particularly ones that involve extensive above-ground running. Most hybrid metro-tram or 'pre-metro' lines whose routes include tracks on city streets or in other publicly accessible areas, such as (formerly) line 51 of the Amsterdam Metro , the MBTA Green Line , RTA Rapid Transit in Cleveland, Frankfurt am Main U-Bahn , and San Francisco's Muni Metro , use overhead wire, as

364-622: A tram engine in the UK) at the head of a line of one or more carriages, similar to a small train. Systems with such steam trams included Christchurch , New Zealand; Sydney, Australia; other city systems in New South Wales ; Munich , Germany (from August 1883 on), British India (from 1885) and the Dublin & Blessington Steam Tramway (from 1888) in Ireland. Steam tramways also were used on

455-520: A Vermont blacksmith, had invented a battery-powered electric motor which he later patented. The following year he used it to operate a small model electric car on a short section of track four feet in diameter. Attempts to use batteries as a source of electricity were made from the 1880s and 1890s, with unsuccessful trials conducted in among other places Bendigo and Adelaide in Australia, and for about 14 years as The Hague accutram of HTM in

546-645: A component implicated in the I-35W Mississippi River bridge collapse in Minneapolis in 2007. Traffic restrictions ended in December 2010, and the entire project was completed in late April 2011. The structure is named after former Allegheny County Commissioner and State Representative George Rankin, Jr. of nearby Wilkinsburg . [1] Charles Herold assisted with the removal of the tram tracks. Streetcar A tram (also known as

637-743: A flat slide-pantograph first used in 1895 by the Baltimore and Ohio Railroad The familiar diamond-shaped roller pantograph was devised and patented by John Q. Brown of the Key System shops for their commuter trains which ran between San Francisco and the East Bay section of the San Francisco Bay Area in California . They appear in photographs of the first day of service, 26 October 1903. For many decades thereafter,

728-419: A pantograph is mainly used to power a railway traction unit, there are certain cases where it has a function other than traction: The electric transmission system for modern electric rail systems consists of an upper, weight-carrying wire (known as a catenary ) from which is suspended a contact wire. The pantograph is spring-loaded and pushes a contact shoe up against the underside of the contact wire to draw

819-726: A similar technology, Pirotsky put into service the first public electric tramway in St. Petersburg, which operated only during September 1880. The second demonstration tramway was presented by Siemens & Halske at the 1879 Berlin Industrial Exposition. The first public electric tramway used for permanent service was the Gross-Lichterfelde tramway in Lichterfelde near Berlin in Germany, which opened in 1881. It

910-488: A standard third rail would obstruct street traffic and present too great a risk of electrocution. Among the various exceptions are several tram systems, such as the ones in Bordeaux , Angers , Reims and Dubai that use a proprietary underground system developed by Alstom , called APS , which only applies power to segments of track that are completely covered by the tram. This system was originally designed to be used in

1001-466: A two-wire circuit makes pantographs impractical, and some streetcar networks, such as the Toronto streetcar system , which have frequent turns sharp enough to require additional freedom of movement in their current collection to ensure unbroken contact. However, many of these networks, including Toronto's, are undergoing upgrades to accommodate pantograph operation. Pantographs with overhead wires are now

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1092-946: A well-known tourist attraction . A single cable line also survives in Wellington (rebuilt in 1979 as a funicular but still called the " Wellington Cable Car "). Another system, with two separate cable lines and a shared power station in the middle, operates from the Welsh town of Llandudno up to the top of the Great Orme hill in North Wales , UK. Hastings and some other tramways, for example Stockholms Spårvägar in Sweden and some lines in Karachi , used petrol trams. Galveston Island Trolley in Texas operated diesel trams due to

1183-411: Is an apparatus mounted on the roof of an electric train , tram or electric bus to collect power through contact with an overhead line . The term stems from the resemblance of some styles to the mechanical pantographs used for copying handwriting and drawings. The pantograph is a common type of current collector ; typically, a single or double wire is used, with the return current running through

1274-426: Is brittle, pieces can break off during operation. Poorly-built pantographs can seize the overhead wire and tear it down, and poor-condition wires can damage the pantograph. To prevent this, a pantograph monitoring station can be used. At sustained high speeds, above 300 km/h (190 mph), friction can cause the contact strip to become red hot, which in turn can cause excessive arcing and eventual failure. In

1365-586: Is still in operation in modernised form. The earliest tram system in Canada was built by John Joseph Wright , brother of the famous mining entrepreneur Whitaker Wright , in Toronto in 1883, introducing electric trams in 1892. In the US, multiple experimental electric trams were exhibited at the 1884 World Cotton Centennial World's Fair in New Orleans, Louisiana , but they were not deemed good enough to replace

1456-734: Is the sole survivor of the fleet). In Italy, in Trieste , the Trieste–Opicina tramway was opened in 1902, with the steepest section of the route being negotiated with the help of a funicular and its cables. Cable cars suffered from high infrastructure costs, since an expensive system of cables , pulleys , stationary engines and lengthy underground vault structures beneath the rails had to be provided. They also required physical strength and skill to operate, and alert operators to avoid obstructions and other cable cars. The cable had to be disconnected ("dropped") at designated locations to allow

1547-713: The Bleecker Street Line until its closure in 1917. Pittsburgh, Pennsylvania , had its Sarah Street line drawn by horses until 1923. The last regular mule-drawn cars in the US ran in Sulphur Rock, Arkansas , until 1926 and were commemorated by a U.S. postage stamp issued in 1983. The last mule tram service in Mexico City ended in 1932, and a mule tram in Celaya, Mexico , survived until 1954. The last horse-drawn tram to be withdrawn from public service in

1638-933: The Lamm fireless engines then propelling the St. Charles Avenue Streetcar in that city. The first commercial installation of an electric streetcar in the United States was built in 1884 in Cleveland, Ohio , and operated for a period of one year by the East Cleveland Street Railway Company. The first city-wide electric streetcar system was implemented in 1886 in Montgomery, Alabama , by the Capital City Street Railway Company, and ran for 50 years. In 1888,

1729-546: The Nord-Sud Company rapid transit lines in Paris until the other operating company of the time, Compagnie du chemin de fer métropolitain de Paris , bought out the company and replaced all overhead wiring with the standard third rail system used on other lines. Numerous railway lines use both third rail and overhead power collection along different portions of their routes, generally for historical reasons. They include

1820-756: The North London line and West London lines of London Overground , the Northern City Line of Great Northern , three of the five lines in the Rotterdam Metro network, Metro-North Railroad's New Haven Line , and the Chicago Transit Authority 's Yellow Line . In this last case, the overhead portion was a remnant of the Chicago North Shore and Milwaukee Railroad 's high-speed Skokie Valley Route, and

1911-715: The Richmond Union Passenger Railway began to operate trams in Richmond, Virginia , that Frank J. Sprague had built. Sprague later developed multiple unit control, first demonstrated in Chicago in 1897, allowing multiple cars to be coupled together and operated by a single motorman. This gave rise to the modern subway train. Following the improvement of an overhead "trolley" system on streetcars for collecting electricity from overhead wires by Sprague, electric tram systems were rapidly adopted across

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2002-655: The TGV ) to low-speed urban tram systems. The design operates with equal efficiency in either direction of motion, as demonstrated by the Swiss and Austrian railways whose newest high-performance locomotives, the Re 460 and Taurus , operate with them set in the opposite direction. In Europe the geometry and shape of the pantographs are specified by CENELEC , the European Committee for Electrotechnical Standardization. While

2093-824: The West Midlands Metro in Birmingham , England adopted battery-powered trams on sections through the city centre close to Grade I listed Birmingham Town Hall . Paris and Berne (Switzerland) operated trams that were powered by compressed air using the Mekarski system . Trials on street tramways in Britain, including by the North Metropolitan Tramway Company between Kings Cross and Holloway, London (1883), achieved acceptable results but were found not to be economic because of

2184-419: The rails . Other types of current collectors include the bow collector and the trolley pole . The pantograph, with a low-friction, replaceable graphite contact strip or " shoe " to minimise lateral stress on the contact wire, first appeared in the late 19th century. Early versions include the bow collector , invented in 1889 by Walter Reichel, chief engineer at Siemens & Halske in Germany, and

2275-1189: The 1850s, after which the "animal railway" became an increasingly common feature in the larger towns. The first permanent tram line in continental Europe was opened in Paris in 1855 by Alphonse Loubat who had previously worked on American streetcar lines. The tram was developed in numerous cities of Europe (some of the most extensive systems were found in Berlin, Budapest , Birmingham , Saint Petersburg , Lisbon , London , Manchester , Paris , Kyiv ). The first tram in South America opened in 1858 in Santiago, Chile . The first trams in Australia opened in 1860 in Sydney . Africa's first tram service started in Alexandria on 8 January 1863. The first trams in Asia opened in 1869 in Batavia (Jakarta), Netherlands East Indies (Indonesia) . Limitations of horsecars included

2366-713: The 1894-built horse tram at Victor Harbor in South Australia . New horse-drawn systems have been established at the Hokkaidō Museum in Japan and also in Disneyland . A horse-tram route in Polish gmina Mrozy , first built in 1902, was reopened in 2012. The first mechanical trams were powered by steam . Generally, there were two types of steam tram. The first and most common had a small steam locomotive (called

2457-420: The 1980s. The history of passenger trams, streetcars and trolley systems, began in the early nineteenth century. It can be divided into several distinct periods defined by the principal means of power used. Precursors to the tramway included the wooden or stone wagonways that were used in central Europe to transport mine carts with unflanged wheels since the 1500s, and the paved limestone trackways designed by

2548-427: The 55 took the tracks on Braddock Avenue for the last leg of its trip to East Pittsburgh. A 55 car could also become a 67 car if necessary, and vice versa, by taking each other's route, in either direction. Though not containing a cloverleaf, the western (Whitaker) end of the bridge also had its share of streetcar and highway complexity. A third trolley route, #68 Homestead- Duquesne - Kennywood - McKeesport , utilized

2639-481: The Australian state of Queensland between 1909 and 1939. Stockholm , Sweden, had a steam tram line at the island of Södermalm between 1887 and 1901. Tram engines usually had modifications to make them suitable for street running in residential areas. The wheels, and other moving parts of the machinery, were usually enclosed for safety reasons and to make the engines quieter. Measures were often taken to prevent

2730-462: The British newspaper Newcastle Daily Chronicle reported that, "A large number of London's discarded horse tramcars have been sent to Lincolnshire where they are used as sleeping rooms for potato pickers ". Horses continued to be used for light shunting well into the 20th century, and many large metropolitan lines lasted into the early 20th century. New York City had a regular horsecar service on

2821-774: The Entertainment Centre, and work is progressing on further extensions. Sydney re-introduced trams (or light rail) on 31 August 1997. A completely new system, known as G:link , was introduced on the Gold Coast, Queensland , on 20 July 2014. The Newcastle Light Rail opened in February 2019, while the Canberra light rail opened on 20 April 2019. This is the first time that there have been trams in Canberra, even though Walter Burley Griffin 's 1914–1920 plans for

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2912-583: The Irish coach builder John Stephenson , in New York City which began service in the year 1832. The New York and Harlem Railroad's Fourth Avenue Line ran along the Bowery and Fourth Avenue in New York City. It was followed in 1835 by the New Orleans and Carrollton Railroad in New Orleans, Louisiana , which still operates as the St. Charles Streetcar Line . Other American cities did not follow until

3003-545: The Netherlands. The first trams in Bendigo, Australia, in 1892, were battery-powered, but within as little as three months they were replaced with horse-drawn trams. In New York City some minor lines also used storage batteries. Then, more recently during the 1950s, a longer battery-operated tramway line ran from Milan to Bergamo . In China there is a Nanjing battery Tram line and has been running since 2014. In 2019,

3094-789: The North Sydney line from 1886 to 1900, and the King Street line from 1892 to 1905. In Dresden , Germany, in 1901 an elevated suspended cable car following the Eugen Langen one-railed floating tram system started operating. Cable cars operated on Highgate Hill in North London and Kennington to Brixton Hill in South London. They also worked around "Upper Douglas" in the Isle of Man from 1897 to 1929 (cable car 72/73

3185-747: The Romans for heavy horse and ox-drawn transportation. By the 1700s, paved plateways with cast iron rails were introduced in England for transporting coal, stone or iron ore from the mines to the urban factories and docks. The world's first passenger train or tram was the Swansea and Mumbles Railway , in Wales , UK. The British Parliament passed the Mumbles Railway Act in 1804, and horse-drawn service started in 1807. The service closed in 1827, but

3276-413: The Second Street Cable Railroad, which operated from 1885 to 1889, and the Temple Street Cable Railway, which operated from 1886 to 1898. From 1885 to 1940, the city of Melbourne , Victoria, Australia operated one of the largest cable systems in the world, at its peak running 592 trams on 75 kilometres (47 mi) of track. There were also two isolated cable lines in Sydney , New South Wales, Australia;

3367-562: The UK at Lytham St Annes , Trafford Park , Manchester (1897–1908) and Neath , Wales (1896–1920). Comparatively little has been published about gas trams. However, research on the subject was carried out for an article in the October 2011 edition of "The Times", the historical journal of the Australian Association of Timetable Collectors, later renamed the Australian Timetable Association. The world's first electric tram line operated in Sestroretsk near Saint Petersburg invented and tested by inventor Fyodor Pirotsky in 1875. Later, using

3458-410: The UK took passengers from Fintona railway station to Fintona Junction one mile away on the main Omagh to Enniskillen railway in Northern Ireland. The tram made its last journey on 30 September 1957 when the Omagh to Enniskillen line closed. The "van" is preserved at the Ulster Transport Museum . Horse-drawn trams still operate on the 1876-built Douglas Bay Horse Tramway on the Isle of Man , and at

3549-434: The UK, the pantographs ( Brecknell Willis and Stone Faiveley ) of vehicles are raised by air pressure and the graphite contact "carbons" create an air gallery in the pantograph head which release the air if a graphite strip is lost, activating the automatic drop device and lowering the pantograph to prevent damage. Newer electric traction units may use more sophisticated methods which detect the disturbances caused by arcing at

3640-508: The advantages over earlier forms of transit was the low rolling resistance of metal wheels on steel rails, allowing the trams to haul a greater load for a given effort. Another factor which contributed to the rise of trams was the high total cost of ownership of horses. Electric trams largely replaced animal power in the late 19th and early 20th centuries. Improvements in other vehicles such as buses led to decline of trams in early to mid 20th century. However, trams have seen resurgence since

3731-423: The bridge. Route 55 was converted to bus on September 5, 1965, ending trolley service over the Rankin Bridge and its ramps. Route 67 cars made their last runs on January 28, 1967, while route 68 had been converted to bus earlier, on September 21, 1958. The Rankin Bridge has been upgraded several times, including at least two redeckings, plus creation of new dual southbound through lanes for PA 837 and conversion of

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3822-460: The busiest tram line in Europe, with a tram running once per minute at rush hour. Bucharest and Belgrade ran a regular service from 1894. Ljubljana introduced its tram system in 1901 – it closed in 1958. Oslo had the first tramway in Scandinavia , starting operation on 2 March 1894. The first electric tramway in Australia was a Sprague system demonstrated at the 1888 Melbourne Centennial Exhibition in Melbourne ; afterwards, this

3913-439: The capital then in the planning stage did propose a Canberra tram system. In Japan, the Kyoto Electric railroad was the first tram system, starting operation in 1895. By 1932, the network had grown to 82 railway companies in 65 cities, with a total network length of 1,479 km (919 mi). By the 1960s the tram had generally died out in Japan. Two rare but significant alternatives were conduit current collection , which

4004-458: The car up the hill at a steady pace, unlike a low-powered steam or horse-drawn car. Cable cars do have wheel brakes and track brakes , but the cable also helps restrain the car to going downhill at a constant speed. Performance in steep terrain partially explains the survival of cable cars in San Francisco. The San Francisco cable cars , though significantly reduced in number, continue to provide regular transportation service, in addition to being

4095-402: The cars to coast by inertia, for example when crossing another cable line. The cable then had to be "picked up" to resume progress, the whole operation requiring precise timing to avoid damage to the cable and the grip mechanism. Breaks and frays in the cable, which occurred frequently, required the complete cessation of services over a cable route while the cable was repaired. Due to overall wear,

4186-409: The city's hurricane-prone location, which would have resulted in frequent damage to an electrical supply system. Although Portland, Victoria promotes its tourist tram as being a cable car it actually operates using a diesel motor. The tram, which runs on a circular route around the town of Portland, uses dummies and salons formerly used on the Melbourne cable tramway system and since restored. In

4277-473: The classic tramway built in the early 20th century with the tram system operating in mixed traffic, and the later type which is most often associated with the tram system having its own right of way. Tram systems that have their own right of way are often called light rail but this does not always hold true. Though these two systems differ in their operation, their equipment is much the same. Pantograph (transport) A pantograph (or " pan " or " panto ")

4368-408: The collectors mounted on horizontally extending pantographs. On lines where open wagons are loaded from above, the overhead line may be offset to allow this; the pantographs are then mounted at an angle to the vertical. Contact between a pantograph and an overhead line is usually assured through a block of graphite . This material conducts electricity while working as a lubricant . As graphite

4459-416: The combined coal consumption of the stationary compressor and the onboard steam boiler. The Trieste–Opicina tramway in Trieste operates a hybrid funicular tramway system. Conventional electric trams are operated in street running and on reserved track for most of their route. However, on one steep segment of track, they are assisted by cable tractors, which push the trams uphill and act as brakes for

4550-462: The cost and unique maintenance needs for what only represented a very small portion of the system, the overhead system was removed and replaced with the same third rail power that was used throughout the rest of the system, which allowed all of Chicago's railcars to operate on the line. All the pantographs were removed from the Skokie equipped cars. Until 2010, the Oslo Metro line 1 changed from third rail to overhead line power at Frøen station. Due to

4641-531: The current needed to run the train. The steel rails of the tracks act as the electrical return . As the train moves, the contact shoe slides along the wire and can set up standing waves in the wires which break the contact and degrade current collection. This means that on some systems adjacent pantographs are not permitted. Pantographs are the successor technology to trolley poles , which were widely used on early streetcar systems. Trolley poles are still used by trolleybuses , whose freedom of movement and need for

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4732-421: The dominant form of current collection for modern electric trains because, although more fragile than a third rail system, they allow the use of higher voltages. Pantographs are typically operated by compressed air from the vehicle's braking system, either to raise the unit and hold it against the conductor or, when springs are used to effect the extension, to lower it. As a precaution against loss of pressure in

4823-430: The downhill run. For safety, the cable tractors are always deployed on the downhill side of the tram vehicle. Similar systems were used elsewhere in the past, notably on the Queen Anne Counterbalance in Seattle and the Darling Street wharf line in Sydney. In the mid-20th century many tram systems were disbanded, replaced by buses, trolleybuses , automobiles or rapid transit . The General Motors streetcar conspiracy

4914-446: The engines from emitting visible smoke or steam. Usually the engines used coke rather than coal as fuel to avoid emitting smoke; condensers or superheating were used to avoid emitting visible steam. A major drawback of this style of tram was the limited space for the engine, so that these trams were usually underpowered. Steam trams faded out around the 1890s to 1900s, being replaced by electric trams. Another motive system for trams

5005-429: The entire length of cable (typically several kilometres) had to be replaced on a regular schedule. After the development of reliable electrically powered trams, the costly high-maintenance cable car systems were rapidly replaced in most locations. Cable cars remained especially effective in hilly cities, since their nondriven wheels did not lose traction as they climbed or descended a steep hill. The moving cable pulled

5096-579: The entire section of its route that runs on the surface, while switching to third rail power before entering the underground portion of its route. The entire metro systems of Sydney , Madrid , Barcelona , Porto , Shanghai , Hong Kong , Seoul , Kobe , Fukuoka , Sendai , Jaipur , Chennai , Mumbai and Delhi use overhead wiring and pantographs (as well as certain lines of the metro systems in Beijing , Chongqing , Noida , Hyderabad , Jakarta , Tokyo , Osaka , Nagoya , Singapore , Sapporo , Budapest , and Mexico City ). Pantographs were also used on

5187-439: The fact that any given animal could only work so many hours on a given day, had to be housed, groomed, fed and cared for day in and day out, and produced prodigious amounts of manure, which the streetcar company was charged with storing and then disposing. Since a typical horse pulled a streetcar for about a dozen miles a day and worked for four or five hours, many systems needed ten or more horses in stable for each horsecar. In 1905

5278-417: The front pantograph was used, debris from an entanglement could cause damage to the rear pantograph, rendering both pantographs and the vehicle inoperable. Automatic dropping device (ADD) is a safety device that automatically lowers the pantograph on electric trains to prevent accidents in case of obstructions or emergencies. It is also known as pantograph dropping device . The automatic dropping device

5369-555: The historic centre of Bordeaux because an overhead wire system would cause a visual intrusion. Similar systems that avoid overhead lines have been developed by Bombardier , AnsaldoBreda , CAF , and others. These may consist of physical ground-level infrastructure, or use energy stored in battery packs to travel over short distances without overhead wiring. Overhead pantographs are sometimes used as alternatives to third rails because third rails can ice over in certain winter weather conditions. The MBTA Blue Line uses pantograph power for

5460-444: The late 19th and early 20th centuries a number of systems in various parts of the world employed trams powered by gas, naphtha gas or coal gas in particular. Gas trams are known to have operated between Alphington and Clifton Hill in the northern suburbs of Melbourne , Australia (1886–1888); in Berlin and Dresden , Germany; in Estonia (1921–1951); between Jelenia Góra , Cieplice , and Sobieszów in Poland (from 1897); and in

5551-402: The late 19th and early 20th centuries. There was one particular hazard associated with trams powered from a trolley pole off an overhead line on the early electrified systems. Since the tram relies on contact with the rails for the current return path, a problem arises if the tram is derailed or (more usually) if it halts on a section of track that has been heavily sanded by a previous tram, and

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5642-437: The main span (the middle two traffic lanes) and the cloverleaf ramps to Kenmawr/Braddock Avenue on the Rankin and Braddock side of the river. In an unusual and complicated, but nevertheless fluid, setup, the tracks of the 55 crossed over the top of, and then interfaced on the surface with, the tracks of another route, #67 Swissvale -Rankin-Braddock , which then left Kenmawr to run on Ridge and Talbot streets in Braddock, while

5733-563: The many level crossings, it was deemed difficult to install a third rail on the rest of the older line's single track . After 2010 third rails were used in spite of level crossings. The third rails have gaps, but there are two contact shoes. On some systems using three phase power supply , locomotives and power cars have two pantographs with the third-phase circuit provided by the running rails. In 1901 an experimental high-speed installation, another design from Walter Reichel at Siemens & Halske, used three vertically mounted overhead wires with

5824-462: The most widely used pantographs are those with a double arm ("made of two rhombs"), but, since the late 1990s, there have been some single-arm pantographs on Russian railways. Some streetcars use double-arm pantographs, among them the Russian KTM-5, KTM-8, LVS-86 and many other Russian-made trams, as well as some Euro-PCC trams in Belgium. American streetcars use either trolley poles or single-arm pantographs. Most rapid transit systems are powered by

5915-475: The necessity of overhead wire and a trolley pole for street cars and railways. While at the University of Denver he conducted experiments which established that multiple unit powered cars were a better way to operate trains and trolleys. Electric tramways spread to many European cities in the 1890s, such as: Sarajevo built a citywide system of electric trams in 1895. Budapest established its tramway system in 1887, and its ring line has grown to be

6006-421: The oldest operating electric tramway in the world. Also in 1883, Mödling and Hinterbrühl Tram was opened near Vienna in Austria. It was the first tram in the world in regular service that was run with electricity served by an overhead line with pantograph current collectors . The Blackpool Tramway was opened in Blackpool, UK on 29 September 1885 using conduit collection along Blackpool Promenade. This system

6097-408: The original 837 through lanes to northbound only. Most recently, the bridge received a $ 47.8 million comprehensive rehabilitation, which included replacement of the concrete deck and the sidewalks. The new deck is wider, allowing for slightly wider lanes, as well as permitting the shoulders to be co-designated as bicycle lanes . Special attention was given to the gusset plates on the bridge structure,

6188-407: The point of contact when the graphite strips are damaged. There are not always two pantographs on an electric multiple unit but, in cases where there are, the other one can be used if one is damaged; an example of this situation would be a Class 390 Pendolino . The rear pantograph in relation to the direction of travel is often used as to avoid damaging both pantographs in case of entanglements: if

6279-415: The poor paving of the streets in American cities which made them unsuitable for horsebuses , which were then common on the well-paved streets of European cities. Running the horsecars on rails allowed for a much smoother ride. There are records of a street railway running in Baltimore as early as 1828, however the first authenticated streetcar in America, was the New York and Harlem Railroad developed by

6370-451: The same diamond shape was used by electric-rail systems around the world and remains in use by some today. The pantograph was an improvement on the simple trolley pole , which prevailed up to that time, primarily because the pantograph allows an electric-rail vehicle to travel at much higher speeds without losing contact with the overhead lines, e.g. due to dewirement of the trolley pole. Notwithstanding this, trolley pole current collection

6461-415: The second case, the arm is held in the down position by a catch. For high-voltage systems, the same air supply is used to "blow out" the electric arc when roof-mounted circuit breakers are used. Pantographs may have either a single or a double arm. Double-arm pantographs are usually heavier, requiring more power to raise and lower, but may also be more fault-tolerant. On railways of the former USSR ,

6552-542: The suburban tramway lines around Milan and Padua ; the last Gamba de Legn ("Peg-Leg") tramway ran on the Milan- Magenta -Castano Primo route in late 1957. The other style of steam tram had the steam engine in the body of the tram, referred to as a tram engine (UK) or steam dummy (US). The most notable system to adopt such trams was in Paris. French-designed steam trams also operated in Rockhampton , in

6643-558: The tracks. Siemens later designed his own version of overhead current collection, called the bow collector . One of the first systems to use it was in Thorold, Ontario , opened in 1887, and it was considered quite successful. While this line proved quite versatile as one of the earliest fully functional electric streetcar installations, it required horse-drawn support while climbing the Niagara Escarpment and for two months of

6734-416: The tram and completing the earth return circuit with their body could receive a serious electric shock. If "grounded", the driver was required to jump off the tram (avoiding simultaneous contact with the tram and the ground) and pull down the trolley pole, before allowing passengers off the tram. Unless derailed, the tram could usually be recovered by running water down the running rails from a point higher than

6825-466: The tram loses electrical contact with the rails. In this event, the underframe of the tram, by virtue of a circuit path through ancillary loads (such as interior lighting), is live at the full supply voltage, typically 600 volts DC. In British terminology, such a tram was said to be 'grounded'—not to be confused with the US English use of the term, which means the exact opposite. Any person stepping off

6916-427: The tram, the water providing a conducting bridge between the tram and the rails. With improved technology, this ceased to be an problem. In the 2000s, several companies introduced catenary-free designs: Alstom's Citadis line uses a third rail, Bombardier's PRIMOVE LRV is charged by contactless induction plates embedded in the trackway and CAF URBOS tram uses ultracaps technology As early as 1834, Thomas Davenport ,

7007-419: The western approach, though not the bridge itself, going straight on PA 837 (Monongahela Boulevard) while the outbound route 55 turned left onto the bridge. The connection was an at-grade three-way "T" junction; the seldom-used third leg allowed route 68 cars to cross the bridge. This junction was made without conflicts with auto traffic, as through traffic on Mon Boulevard (today's northbound lanes) passed under

7098-804: The wider term light rail , which also includes systems separated from other traffic. Tram vehicles are usually lighter and shorter than main line and rapid transit trains. Most trams use electrical power, usually fed by a pantograph sliding on an overhead line ; older systems may use a trolley pole or a bow collector . In some cases, a contact shoe on a third rail is used. If necessary, they may have dual power systems—electricity in city streets and diesel in more rural environments. Occasionally, trams also carry freight . Some trams, known as tram-trains , may have segments that run on mainline railway tracks, similar to interurban systems. The differences between these modes of rail transport are often indistinct, and systems may combine multiple features. One of

7189-409: The winter when hydroelectricity was not available. It continued in service in its original form into the 1950s. Sidney Howe Short designed and produced the first electric motor that operated a streetcar without gears. The motor had its armature direct-connected to the streetcar 's axle for the driving force. Short pioneered "use of a conduit system of concealed feed" thereby eliminating

7280-532: The world's first hydrogen fuel cell vehicle tramcar at an assembly facility in Qingdao . The chief engineer of the CSR subsidiary CSR Sifang Co Ltd. , Liang Jianying, said that the company is studying how to reduce the running costs of the tram. Trams have been used for two main purposes: for carrying passengers and for carrying cargo. There are several types of passenger tram: There are two main types of tramways,

7371-401: The world. Earlier electric trains proved difficult or unreliable and experienced limited success until the second half of the 1880s, when new types of current collectors were developed. Siemens' line, for example, provided power through a live rail and a return rail, like a model train , limiting the voltage that could be used, and delivering electric shocks to people and animals crossing

7462-682: Was a case study of the decline of trams in the United States. In the 21st century, trams have been re-introduced in cities where they had been closed down for decades (such as Tramlink in London), or kept in heritage use (such as Spårväg City in Stockholm). Most trams made since the 1990s (such as the Bombardier Flexity series and Alstom Citadis ) are articulated low-floor trams with features such as regenerative braking . In March 2015, China South Rail Corporation (CSR) demonstrated

7553-491: Was built by Werner von Siemens who contacted Pirotsky. This was the world's first commercially successful electric tram. It drew current from the rails at first, with overhead wire being installed in 1883. In Britain, Volk's Electric Railway was opened in 1883 in Brighton. This two kilometer line along the seafront, re-gauged to 2 ft  8 + 1 ⁄ 2  in ( 825 mm ) in 1884, remains in service as

7644-487: Was installed as a commercial venture operating between the outer Melbourne suburb of Box Hill and the then tourist-oriented country town Doncaster from 1889 to 1896. Electric systems were also built in Adelaide , Ballarat , Bendigo , Brisbane , Fremantle , Geelong , Hobart , Kalgoorlie , Launceston , Leonora , Newcastle , Perth , and Sydney . By the 1970s, the only full tramway system remaining in Australia

7735-621: Was restarted in 1860, again using horses. It was worked by steam from 1877, and then, from 1929, by very large (106-seat) electric tramcars, until closure in 1960. The Swansea and Mumbles Railway was something of a one-off however, and no street tramway appeared in Britain until 1860 when one was built in Birkenhead by the American George Francis Train . Street railways developed in America before Europe, due to

7826-628: Was tested in San Francisco , in 1873. Part of its success is attributed to the development of an effective and reliable cable grip mechanism, to grab and release the moving cable without damage. The second city to operate cable trams was Dunedin , from 1881 to 1957. The most extensive cable system in the US was built in Chicago in stages between 1859 and 1892. New York City developed multiple cable car lines, that operated from 1883 to 1909. Los Angeles also had several cable car lines, including

7917-635: Was the Melbourne tram system. However, there were also a few single lines remaining elsewhere: the Glenelg tram line , connecting Adelaide to the beachside suburb of Glenelg , and tourist trams in the Victorian Goldfields cities of Bendigo and Ballarat. In recent years the Melbourne system, generally recognised as the largest urban tram network in the world, has been considerably modernised and expanded. The Adelaide line has been extended to

8008-411: Was the cable car, which was pulled along a fixed track by a moving steel cable, the cable usually running in a slot below the street level. The power to move the cable was normally provided at a "powerhouse" site a distance away from the actual vehicle. The London and Blackwall Railway , which opened for passengers in east London, England, in 1840 used such a system. The first practical cable car line

8099-661: Was the only line on the entire Chicago subway system to utilize pantograph collection for any length. As such, the line required railcars that featured pantographs as well as third rail shoes, and since the overhead was a very small portion of the system, only a few cars would be so equipped. The changeover occurred at the grade crossing at East Prairie, the former site of the Crawford-East Prairie station . Here, trains bound for Dempster-Skokie would raise their pantographs, while those bound for Howard would lower theirs, doing so at speed in both instances. In 2005, due to

8190-657: Was used successfully at up to 140 km/h (90 mph) on the Electroliner vehicles of the Chicago North Shore and Milwaukee Railroad , also known as the North Shore Line. The most common type of pantograph today is the so-called half-pantograph (sometimes Z-shaped), which evolved to provide a more compact and responsive single-arm design at high speeds as trains got faster. Louis Faiveley invented this type of pantograph in 1955. The half-pantograph can be seen in use on everything from very fast trains (such as

8281-823: Was widely used in London, Washington, D.C., and New York City, and the surface contact collection method, used in Wolverhampton (the Lorain system), Torquay and Hastings in the UK (the Dolter stud system), and in Bordeaux , France (the ground-level power supply system). The convenience and economy of electricity resulted in its rapid adoption once the technical problems of production and transmission of electricity were solved. Electric trams largely replaced animal power and other forms of motive power including cable and steam, in

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