Standard gauge

Track gauge

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Minimum   Fifteen inch 381 mm (15 in) Narrow   600 mm, Two foot 597 mm 600 mm 603 mm 610 mm (1 ft 11 1⁄2 in) (1 ft 11 5⁄8 in) (1 ft 11 3⁄4 in) (2 ft)   750 mm, Bosnian, Two foot six inch, 800 mm 750 mm 760 mm 762 mm 800 mm (2 ft 5 1⁄2 in) (2 ft 5 15⁄16 in) (2 ft 6 in) (2 ft 7 1⁄2 in)   Swedish three foot, 900 mm, Three foot 891 mm 900 mm 914 mm (2 ft11 3⁄32 in) (2 ft 11 7⁄16) (3 ft)   Metre 1,000 mm (3 ft 3 3⁄8 in)   Three foot six inch, Cape, CAP, Kyōki 1,067 mm (3 ft 6 in)   Four foot six inch 1,372 mm (4 ft 6 in)   Standard 1,435 mm (4 ft 8 1⁄2 in) Broad   Russian, Five foot 1,520 mm 1,524 mm (4 ft 11 27⁄32 in) (5 ft)   Irish 1,600 mm (5 ft 3 in)   Iberian 1,668 mm (5 ft 5 21⁄32 in)   Indian 1,676 mm (5 ft 6 in)   Six foot 1,829 mm (6 ft)   Brunel 2,140 mm (7 ft 1⁄4 in)
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The standard gauge (also Stephenson gauge after George Stephenson, International gauge or normal gauge) is a widely used railway track gauge. Approximately 60% of lines in the world are this gauge (see the list of standard gauge usages). All high-speed lines except Russia, Uzbekistan, Finland are standard gauge. The distance between the inside edges of the rails is defined to be 1,435 millimetres (4 ft 8 ¹⁄₂ in). In the United States and Canada, it is still defined in imperial units, 4 feet 8 ¹⁄₂ inches (1,435.1 mm). It is also called UIC gauge, or UIC track gauge,^[1][2][3] the European gauge in the EU^[4] and Russia,^[5] or uniform gauge in Queensland.

History

As railways developed and expanded one of the key issues was track gauge (the distance, or width, between the inner sides of the rails) to be used. The result was the adoption throughout a large part of the world of a “standard gauge” of 4 ft 8 ¹⁄₂ in allowing inter-connectivity and inter-operability.

In England some early lines in colliery (coal mining) areas in the northeast were 4 ft 8 in (1,422 mm); and in Scotland some early lines were 4 ft 6 in (1,372 mm) (Scotch gauge). By 1846, in both countries, these lines were widened to standard gauge. Parts of the United States, mainly in the Northeast, adopted the same gauge because some early trains were purchased from Britain. However, until well into the second half of the 19th century Britain and the USA had several different track gauges. The American gauges converged as the advantages of equipment interchange became increasingly apparent; notably, the South's 5 ft (1,524 mm) broad gauge was converted to be compatible with standard gauge over the course of two days beginning 31 May 1886.^[6] See Track gauge in the United States.

With the advent of metrication, standard gauge was redefined as 1,435 mm,^[7] a reduction of 0.1 mm, but well within existing tolerance limits. The exception is the United States, where standard gauge continues to be defined in terms of customary units.

Origins

A popular legend that has been around since at least 1937^[8] traces the origin of the 4 ft 8 ¹⁄₂ in gauge even further back than the coalfields of northern England, pointing to the evidence of rutted roads marked by chariot wheels dating from the Roman Empire.^{[lower-alpha 1]} Snopes categorized this legend as false but commented that “... it is perhaps more fairly labelled as 'True, but for trivial and unremarkable reasons.'"^[9] The historical tendency to place the wheels of horse-drawn vehicles approximately 5 feet (1,500 mm) apart probably derives from the width needed to fit a carthorse in between the shafts.^[9] In addition, while road-traveling vehicles are typically measured from the outermost portions of the wheel rims (and there is some evidence that the first railroads were measured in this way as well), it became apparent that for vehicles travelling on rails it was better to have the wheel flanges located inside the rails, and thus the distance measured on the inside of the wheels (and, by extension, the inside faces of the rail heads), was the important one.

There was no standard gauge for horse railways, but there were rough groupings: in the north of England none were less than 4 ft (1,219 mm).^[10] Wylam colliery's system, built before 1763, was 5 ft (1,524 mm); as was John Blenkinsop's Middleton Railway, the old 4 ft (1,219 mm) plateway was relaid to 5 ft (1,524 mm) so that Blenkinsop's engine could be used.^[10] Others were 4 ft 4 in (1,321 mm) Beamish or 4 ft 7 ¹⁄₂ in (Bigges Main and Kenton and Coxlodge).^[10]

The English railway pioneer George Stephenson spent much of his early engineering career working for the coal mines of County Durham. He favoured 4 ft 8 in (1,422 mm) for wagonways in Northumberland and Durham and used it on his Killingworth line.^[10] The Hetton and Springwell wagonways also used this gauge.

Stephenson's Stockton and Darlington railway (S&DR) was built primarily to transport coal from mines near Shildon to the port at Stockton-on-Tees. The initial gauge of 4 ft 8 in (1,422 mm) was set to accommodate the existing gauge of hundreds of horse-drawn chaldron wagons^[11] that were already in use on the wagonways in the mines. The railway used this gauge for 15 years before a change was made to 4 ft 8 ¹⁄₂ in gauge.^[10][12] The historic Mount Washington Cog Railway, the world's first mountain-climbing rack railway, is still in operation in the 21st century, and has used the earlier 4 ft 8 in gauge since its inauguration in 1868.

The beginnings of the 4 ft 8 ¹⁄₂ in gauge

George Stephenson used the 4 ft 8 ¹⁄₂ in gauge (including a belated extra ¹⁄₂ in (13 mm) of free movement to reduce binding on curves^[12]) for the Liverpool and Manchester Railway, authorised in 1826 and opened 30 September 1830. The success of this project led to George Stephenson and his son Robert being employed to engineer several other larger railway projects.

Non-standard gauge

• Monkland and Kirkintilloch Railway, authorised 1824, opened 1825, used 4 ft 6 in (1,372 mm).
• Dundee and Newtyle Railway, authorised 1829, opened 1831, used 4 ft 6 ¹⁄₂ in (1,384 mm).
• the Eastern Counties Railway, authorised on 4 July 1836, used 5 ft (1,524 mm)^[13]
• the London and Blackwall Railway, authorised on 28 July 1836, used 5 ft ¹⁄₂ in (1,537 mm);^[14][15][16]
• the Dundee and Arbroath Railway, incorporated on 19 May 1836, opened October 1838, used 5 ft 6 in (1,676 mm) until standardised in 1847.
• the Arbroath and Forfar Railway, incorporated on 19 May 1836, opened November 1838, used 5 ft 6 in.
• the Northern and Eastern Railway, authorised on 4 July 1836, used 5 ft (1,524 mm) gauge.^[17]
• Aberdeen Railway, opened 1848, used 5 ft 6 in (1,676 mm) until standardised.

Almost standard gauge

• the Killingworth Colliery tramway; 4 ft 8 in (1,422 mm) ^[18]
• the Hetton colliery railway; opened 1822; engineered by George Stephenson 4 ft 8 in (1,422 mm) ^[18]
• the Stockton and Darlington Railway; opened 1825; original gauge 4 ft 8 in (1,422 mm)
• the Chester and Birkenhead Railway, authorised on 12 July 1837, used 4 ft 9 in (1,448 mm);^[19]
• the London and Brighton Railway, authorised on 15 July 1837, used 4 ft 9 in (1,448 mm);^[20]
• the Manchester and Birmingham Railway, authorised on 30 June 1837, used 4 ft 9 in (1,448 mm);^[21]
• the Manchester and Leeds Railway, authorised on 4 July 1836, used 4 ft 9 in (1,448 mm)^[22] and
  • The 4 ft 9 in (1,448 mm) railways were intended to take 4 ft 8 ¹⁄₂ in (1,435 mm) gauge vehicles and allow a (second) running tolerance.
• The Trams in Dresden, authorized in 1872 as horsecars, used 1,440 mm (4 ft 8 ¹¹⁄₁₆ in) gauge vehicles. Converted to 600V DC electric trams in 1893, uses 1,450 mm (4 ft 9 ³⁄₃₂ in); both gauges are within the tolerance for standard gauge

Standard gauge

• the Bolton and Leigh Railway, authorised 1825, opened 1828; connected to LMR.
• the Saint-Étienne–Lyon railway, commenced 1826, opened 1833.
• the Grand Junction Railway, authorised 1833, opened 1837; connected to LMR.
• the Newcastle & Carlisle Railway, authorised 1829, opened 1834; isolated from LMR, engineered by Robert Stephenson
• the Manchester and Birmingham Railway, authorised 1837, opened 1840; connected to LMR.
• the London and Birmingham Railway, authorised 1833, opened 1838, connected to LMR.
• the Birmingham and Gloucester Railway, authorised 1836, open 1840, connected to LMR.
• the London and Southampton Railway, authorised 1834, open 1840.
• the London and Brighton Railway, authorised 1837, open 1841.
• the South Eastern Railway, authorised 1836, open 1844.

During the "gauge war" with the Great Western Railway, standard gauge was called "narrow gauge". The modern use of narrow gauge for gauges less than standard did not arise for 20 years, until the first such locomotive-hauled passenger railway, the Festiniog.

Dual gauge

• Cheltenham and Great Western Union Railway—authorised 1836; opened 1840; dual gauge 1843 1,435 mm (4 ft 8 ¹⁄₂ in) and 7 ft ¹⁄₄ in (2,140 mm).

The Royal Commission

In 1845, in the United Kingdom of Great Britain and Ireland, a Royal Commission on Railway Gauges reported in favour of a standard gauge. In Great Britain, Stephenson's gauge was chosen on the grounds that lines of this gauge were eight times longer than those of the rival 7 ft (2,134 mm)7 ft ¹⁄₄ in gauge adopted principally by the Great Western Railway. The subsequent Gauge Act ruled that new passenger-carrying railways in Great Britain should be built to a standard gauge of 1,435 mm (4 ft 8 ¹⁄₂ in), and those in Ireland to a new standard gauge of 5 ft 3 in (1,600 mm). It allowed the broad-gauge companies in Great Britain to continue with their tracks and expanding their networks within the "Limits of Deviation" and the exceptions defined in the Act. After an intervening period of mixed-gauge operation (tracks were laid with three rails), the Great Western Railway finally converted its entire network to standard gauge in 1892.

The Royal Commission made no comment about small to-be-called "narrow"-gauge lines, such as the Festiniog Railway, which allowed a future multiplicity of small gauges in the UK; it also made no comments about future gauges in British colonies.

Regrets

Robert Stephenson was reported to have said that if he had a second chance to choose a standard gauge, he would choose one wider than 1,435 mm (4 ft 8 ¹⁄₂ in).^[23][24] "I would take a few inches more, but a very few".^[25]

Modern almost-standard gauge railways

• The Mount Washington Cog Railway, the world's oldest cog railway (1868) and still in operation, uses a slightly-narrower 4 ft 8 in (1,422 mm) gauge.
• The MTR in Hong Kong uses 1,432 mm (4 ft 8 ³⁄₈ in) except on the East Rail, West Rail, Ma On Shan lines, and Light Rail
• The Toronto streetcar system uses 4 ft 10 ⁷⁄₈ in (1,495 mm) Toronto gauge
• The Washington Metro uses 4 ft 8 ¹⁄₄ in (1,429 mm)

Road vehicles

Several states in the United States had laws requiring road vehicles to have a consistent gauge to allow them to follow ruts in the road. These gauges were similar to railway standard gauge.^[26]

Legislation

• United Kingdom: Regulating the Gauge of Railways Act 1846

Installations

See also

• Standard Gauge (toy trains)

Notes

References

Footnotes

Works cited

Further reading