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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 55% of the lines in the world are this gauge (see the list of standard gauge usages). All high-speed rail lines (except those in Russia, Uzbekistan, India, and 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) (except in the United States and Canada, where it is still defined in Imperial and US customary units as 4 feet 8 1⁄2 inches (1,435.1 mm)). It is also called the UIC gauge or UIC track gauge, the European gauge in the EU and Russia, or uniform gauge in Queensland.
- 1 History
- 2 Modern almost-standard gauge railways
- 3 Road vehicles
- 4 Legislation
- 5 Installations
- 6 See also
- 7 Notes
- 8 References
- 9 Further reading
- 10 External links
As railways developed and expanded, one of the key issues was the 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). In both countries, these lines had been widened to standard gauge by 1846. 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 used 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 on 31 May 1886. See Track gauge in the United States.
With the advent of metrication, standard gauge was redefined as 1,435 mm, a reduction of 0.1 mm but well within existing tolerance limits, with the exception of the United States and Canada, where standard gauge continues to be defined in terms of feet and inches.
A popular legend that has been around since at least 1937 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.[a]  Snopes categorized this legend as "false", but commented that “... it is perhaps more fairly labelled as 'True, but for trivial and unremarkable reasons.'" 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. 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). 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. Others were 4 ft 4 in (1,321 mm) (in Beamish) or 4 ft 7 1⁄2 in (Bigges Main and Kenton and Coxlodge).
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. 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 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. 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) for the Liverpool and Manchester Railway, authorised in 1826 and opened 30 September 1830. The success of this project led to Stephenson and his son Robert being employed to engineer several other larger railway projects.
- Monkland and Kirkintilloch Railway, authorised 1824 and opened 1825, used 4 ft 6 in (1,372 mm).
- Dundee and Newtyle Railway, authorised 1829 and 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)
- the London and Blackwall Railway, authorised on 28 July 1836, used 5 ft 1⁄2 in (1,537 mm).
- the Dundee and Arbroath Railway, incorporated on 19 May 1836 and 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 and 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.
- Aberdeen Railway, opened 1848, used 5 ft 6 in (1,676 mm) until standardised.
Almost standard gauge
- the Killingworth Colliery tramway, used 4 ft 8 in (1,422 mm).
- the Hetton colliery railway, opened 1822, engineered by George Stephenson, used 4 ft 8 in (1,422 mm).
- 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).
- the London and Brighton Railway, authorised on 15 July 1837, used 4 ft 9 in (1,448 mm).
- the Manchester and Birmingham Railway, authorised on 30 June 1837, used 4 ft 9 in (1,448 mm).
- the Manchester and Leeds Railway, authorised on 4 July 1836, used 4 ft 9 in (1,448 mm).
- 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, now uses 1,450 mm (4 ft 9 3⁄32 in); both gauges are within the tolerance for standard gauge.
- trams in Nuremberg nominally used 1,432 mm (4 ft 8 3⁄8 in) during much of their existence, but have since been converted to standard gauge in name as well as fact
- 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, opened 1840, connected to LMR.
- the London and Southampton Railway, authorised 1834, opened 1840.
- the London and Brighton Railway, authorised 1837, opened 1841.
- the South Eastern Railway, authorised 1836, opened 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.
- 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.
Robert Stephenson was reported to have said that if he had had a second chance to choose a standard gauge, he would have chosen one wider than 1,435 mm (4 ft 8 1⁄2 in). "I would take a few inches more, but a very few".
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, and Ma On Shan lines, and on its light rail components.
- 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).
- Trams in Dresden use 1450 mm gauge
- United Kingdom: Regulating the Gauge of Railways Act 1846
|Albania||National rail network||339 km (211 mi)|
|Algeria||National rail network||3,973 km (2,469 mi)|
|Argentina||General Urquiza Railway (except for Ferrocarril Económico Correntino, which uses 600 mm (1 ft 11 5⁄8 in))
Buenos Aires Underground
Tren de la Costa
|Other major lines are mostly 1,676 mm (5 ft 6 in) broad gauge (Indian gauge), with the exception of the metre-gauge General Belgrano Railway.
Further information: Rail transport in Argentina
|Australia||Pacific National, Pilbara Railways
Further information: List of Australian railway companies
|Victoria (Australia) built the first railways to the Irish broad gauge. New South Wales then built to the standard gauge, so trains had to stop on the border and passengers transferred, which was only rectified in the 1960s. Queensland still runs on a narrow gauge but there is a standard gauge line from NSW to Brisbane.
Further information: Rail gauge in Australia
|Austria||Österreichische Bundesbahnen||The Semmering railway has UNESCO World Heritage Site status.|
|Bangladesh||Only used for rapid transit systems: Dhaka Metro|
|Belgium||NMBS/SNCB, Brussels Metro and tramway|
|Bosnia and Herzegovina||Željeznice Federacije Bosne i Hercegovine and Željeznice Republike Srpske,
Further information: Rail transport in Bosnia and Herzegovina
|Brazil||Estrada de Ferro do Amapá; from Uruguaiana to the border with Argentina and from Santana do Livramento to the border with Uruguay (both mixed gauge 1,435 mm and 1,000 mm (3 ft 3 3⁄8 in)); remaining tracks at Jaguarão, Rio Grande do Sul (currently inoperable)||194 km (121 mi)|
|Bulgaria||National Railway Infrastructure Company (NRIC),
Bulgarian State Railways (BDZ),
part of Sofia Tramway system
|Canada||National rail network||49,422 km (30,709 mi)|
|China||National rail network||103,144 km (64,091 mi)|
Further information: Transport in Croatia
|Colombia||Metro de Medellín, Tren del Cerrejón, Metro de Bogotá||
Further information: Metro de Medellín
|Cuba||Ferrocarriles de Cuba|
|Czech Republic||České dráhy,
all tram systems in the country (Liberec has dual gauge 1,000/1,435 mm, with one meter-gauge interurban line to Jablonec nad Nisou),
funicular in Prague
|Denmark||Banedanmark and Copenhagen Metro|
|Djibouti||Addis Ababa-Djibouti Railway|
|Egypt||Egyptian National Railways|
|Ethiopia||Addis Ababa-Djibouti Railway||Other standard gauge lines under construction.|
|France||SNCF, RATP (on RER lines)|
|Germany||Deutsche Bahn, numerous local public transport providers||43,468 km|
|Greece||Hellenic Railways Organisation (operated by TrainOSE)||All modern Greek network, except in the Peloponnese|
|Hong Kong||MTR (former KCR network—East Rail Line, West Rail Line, Ma On Shan Line, Light Rail)||Other MTR lines use 1,432 mm (4 ft 8 3⁄8 in) instead of 4 ft 8 1⁄2 in|
Budapest metro, HÉV (Suburban railway),
Tram systems in Budapest, Debrecen, Miskolc, Szeged,
Budapest Cog-wheel Railway
|India||Only used for rapid transit systems: Bangalore Metro, Chennai Metro, Delhi Metro (Phase 2 onwards), Gurgaon Metro, Hyderabad Metro Rail, Jaipur Metro, Kochi Metro, Kolkata Metro (Line 2 onwards), Trams in Kolkata, Lucknow Metro, Mumbai Metro, Navi Mumbai Metro||Indian heavy rail systems (Indian Railways) use 1,676 mm (5 ft 6 in) Indian broad gauge. The majority of under-construction and future rapid transit systems prefer standard gauge.|
|Indonesia||Railways in Aceh Province|
|Iran||Islamic Republic of Iran Railways|
|Iraq||Iraqi Republic Railways|
|Ireland||Railway Procurement Agency||Luas in Dublin|
|Israel||Israel Railways, CTS, operating the Jerusalem Light Rail|
|Italy||Ferrovie dello Stato|
|Japan||Shinkansen, JR Hokkaido Naebo Works (see Train on Train), Keisei Line, Keikyu Line, Tokyo Metro Ginza Line, Tokyo Metro Marunouchi Line, Toei Asakusa Line, Toei Oedo Line, Kintetsu Corp (not including the Minami-Osaka Line (1,067 mm), etc.), Keihan Railway, Hankyu Railway, Hanshin Railway, Kyoto Municipal Subway, Osaka Municipal Subway.||All other subway lines in Japan, except for the Toei Shinjuku Line (which uses 1,372 mm (4 ft 6 in), scotch gauge) and the Sapporo Subway (a rubber-tired system), use 1,067 mm (3 ft 6 in) (cape gauge).|
|Kenya||Mombasa-Nairobi Standard Gauge Railway||Network under construction|
|Lebanon||All lines out of service and essentially dismantled|
|Libya||Network under construction|
|Luxembourg||Société Nationale des Chemins de Fer Luxembourgeois|
|Malaysia||RapidKL (Kelana Jaya Line, Ampang Line), KLIA Ekspres|
Further information: List of Mexican railroads
|Montenegro||Željeznice Crne Gore||3|
|Morocco||Rail transport in Morocco|
|Netherlands||Nederlandse Spoorwegen and regional railways.|
|Nigeria||Lagos-Kano Standard Gauge Railway||Under construction; Abuja to Kaduna section operational.|
|North Korea||Railways of the DPRK.|
|Norway||Norwegian National Rail Administration, Rail transport in Norway|
|Panama||Panama Railway||Regauged from 5 ft (1,524 mm) in 2001|
|Paraguay||Ferrocarril Presidente Don Carlos Antonio López, now Ferrocarril de Paraguay S.A. (FEPASA)||36 km out of Asunción (used as a tourist steam line), plus 5 km from Encarnación to the border with Argentina, carrying mainly exported soy; the rest of the 441-km line awaits its fate, while redevelopment plans come and go with regularity. The section from west of Encarnación to north of San Salvador, plus the entire San Salvador–Abaí branch, have been dismantled by the railway itself and sold for scrap to raise funds.|
|Peru||Railroad Development Corporation, Ferrocarril Central Andino (Callao–Lima–La Oroya–Huancayo and La Oroya–Cerro del Pasco lines), Ferrocarril del sur de Peru (operated by Peru Rail) Matarani–Arequipa–Puno and Puno–Cuzco, Ilo–Moquegua mining railroad, Tacna–Arica (Chile) international line, (operated by Tacna province), Lima electric suburban railway|
|Philippines||Manila LRT Lines 1 and 2, and Manila MRT Line 3.|
|Poland||Polskie Koleje Państwowe, Warsaw Metro, most tramway systems throughout the country|
|Portugal||Planned high-speed lines, Braga and Oporto (Guindais) funiculars, Lisbon Metro, Oporto Metro (partly adapted from former 1,000 mm tracks), Metro Transportes do Sul light rail in Almada.||All other railways use 1,668 mm (5 ft 5 2⁄3 in) (broad gauge); some use 1,000 mm (3 ft 3 3⁄8 in) (meter gauge); Decauville uses 500 mm gauge.|
|Romania||Căile Ferate Române|
|Russia||Rostov-on-Don tramway, lines connecting Kaliningrad with Poland|
|Saudi Arabia||Rail transport in Saudi Arabia|
|Slovakia||Železnice Slovenskej republiky, Košice tramway system|
|South Africa||Gautrain in Gauteng Province||Rest of country uses Cape gauge|
|Spain||AVE high-speed rail lines from Madrid to Seville, Málaga, Saragossa, Barcelona (-Perthus), Toledo, Huesca, and Valladolid, Barcelona Metro (L2, L3, L4, and L5 lines), Barcelona FGC (lines L6 and L7), and Metro Vallès (lines S1, S2, S5, and S55).||All other railways use 1,668 mm (5 ft 5 2⁄3 in) (broad gauge) and/or 1,000 mm (3 ft 3 3⁄8 in) (meter gauge).|
|Sweden||Swedish Transport Administration, Storstockholms Lokaltrafik (Stockholm metro, commuter and light rail lines), tram networks in Gothenburg and Norrköping|
|Switzerland||Swiss Federal Railways, BLS, Rigi Railways (rack railway)|
|Syria||Chemins de Fer Syriens|
|Taiwan||Taipei Rapid Transit System, Taiwan High Speed Rail, and Kaohsiung Mass Rapid Transit|
|Thailand||Bangkok Skytrain, Bangkok Metro, and Suvarnabhumi Airport Link|
|Tunisia||Northern part of the network|
|Turkey||Turkish State Railways (also operates Marmaray), metro networks, and tram networks||Some tram networks use metre gauge.
Further information: Rail transport in Turkey
|United Arab Emirates||Rail transport in the United Arab Emirates|
|United Kingdom (Great Britain)||Entire rail network in Great Britain (but not Ireland) since standardisation by the Regulating the Gauge of Railways Act 1846|
|United States||Modern national railroad network; see Track gauge in the United States||The Washington Metro uses 4 ft 8 1⁄4 in (1,429 mm) gauge, which is 6 mm (1⁄4″) narrower than standard gauge.|
|Uruguay||National rail network|
|Vietnam||North of Hanoi||Includes dual gauge (standard/metre) to the Chinese border.|
- The gaps in the pedestrian crossings in Pompeii could give credence or otherwise to this statement, but no relevant studies appear to have been made.
- Francesco FALCO (23 January 2013). "EU support to help convert the Port of Barcelona’s rail network to UIC gauge". TEN-T Executive Agency. Retrieved 20 August 2013.
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- Whishaw (1842), p. 260.
- Whishaw (1842), p. 363.
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- "The World Factbook". Retrieved 1 June 2016.
- "The World Factbook". Retrieved 1 June 2016.
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- Allen (1987).[page needed]
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- "Railway Infrastructure". Vietnam Railways. 2005. Retrieved 29 November 2007.
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- Baxter, Bertran (1966). Stone Blocks and Iron Rails (Tramroads). Industrial Archaeology of the British Isles. Newton Abbot: David & Charles.
- Jones, Robin (2013). The Rocket Men. Mortons Media Group. ISBN 9781909128279.
- Jones, Stephen K. (2009). Brunel in South Wales. vol. II: Communications and Coal. Stroud: The History Press. pp. 64–65. ISBN 9780752449128.
- Setti, João Bosco (2008). Brazilian Railroads. Rio de Janeiro: Memória do Trem. ISBN 9788586094095 – via Google Books.
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- Whishaw, Francis (1842). The Railways of Great Britain and Ireland: Practically Described and Illustrated. London: John Weale (republished 1969, David & Charles reprints: Newton Abbot). ISBN 0-7153-4786-1.
- Pomeranz, Kenneth; Topik, Steven (1999). The World that Trade Created: Society, Culture, and World Economy, 1400 to the Present. Armonk, NY: M.E. Sharpe. ISBN 0-7656-0250-4.
- Puffert, Douglas J. (2009). Tracks across Continents, Paths through History: The Economic Dynamics of Standardization in Railway Gauge. University of Chicago Press. ISBN 978-0-226-68509-0.
- "The Sydney Morning Herald". The Sydney Morning Herald. 23 May 1892. p. 4. Retrieved 14 August 2011 – via National Library of Australia., a discussion of gauge in Australia circa 1892
- A learned text of standardisation of gauge
- "Standard Railway Gauge". Townsville Bulletin. 5 October 1937. p. 12. Retrieved 19 March 2014 – via National Library of Australia., a discussion of the Roman gauge origin theory.