Barlow rail was a rolled rail section used on early railways. It has wide flaring feet and was designed to be laid direct on the ballast

Track ballast

Track ballast forms the trackbed upon which railway sleepers or railroad ties are laid. It is packed between, below, and around the ties. It is used to facilitate drainage of water, to distribute the load from the railroad ties, and also to keep down vegetation that might interfere with the track...

, without requiring sleepers

Railroad tie

A railroad tie/railway tie , or railway sleeper is a rectangular item used to support the rails in railroad tracks...

. It was widely adopted on lightly trafficked railways, but was ultimately unsuccessful because of maintenance difficulties.

Usage

In the mid-nineteenth century, railway networks were expanding into areas where lighter traffic was expected. The first cost of conventional railway track was considerable, and cheaper alternatives were sought. The Barlow rail offered this benefit, by avoiding the cost of sleepers and chairs altogether. Laid directly in the ballast, it required no other ancillary equipment; however the rail itself was significantly heavier and more expensive than conventional rails.

In practice it had several disadvantages; in particular there was no gauge tie, so that if the ballast was poorly consolidated, the rails could gradually move independently, resulting in a serious derailment risk. Some modifications involved the provision of tie bars between opposing rails to maintain the gauge

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...

.

The wider and heavier rail section was considerably stiffer to lateral bending, and this made smooth alignment in curves difficult, especially at the joints.

On curves, passing vehicle wheels generate a crabbing effect, tending to push the rails apart, and in the absence of sleepers this tended to rotate the rails outward, that is, they tended to tip outwards.

Inventor

The rail profile was invented in 1849 by W.H.Barlow

William Henry Barlow

On 28 December 1879, the central section of the North British Railway's bridge across the River Tay near Dundee collapsed in the Tay Bridge disaster as an express train crossed it in a heavy storm. All 75 passengers and crew on the train were killed...

, engineer of the Midland Railway

Midland Railway

The Midland Railway was a railway company in the United Kingdom from 1844 to 1922, when it became part of the London, Midland and Scottish Railway....

. The design was patented (12438 of 1849)

On 14 May 1850, he presented a paper to the Institution of Civil Engineers

Institution of Civil Engineers

Founded on 2 January 1818, the Institution of Civil Engineers is an independent professional association, based in central London, representing civil engineering. Like its early membership, the majority of its current members are British engineers, but it also has members in more than 150...

 in London detailing his ideas and stating that a test section of 125lb/yd rail on the Midland Junction Railway had proven satisfactory.

He admitted that there had been difficulty in rolling the section but this had been overcome by the manufacturers at Middlesbrough

Middlesbrough

Middlesbrough is a large town situated on the south bank of the River Tees in north east England, that sits within the ceremonial county of North Yorkshire...

.

Application

The rail section was adopted by Brunel

Isambard Kingdom Brunel

Isambard Kingdom Brunel, FRS , was a British civil engineer who built bridges and dockyards including the construction of the first major British railway, the Great Western Railway; a series of steamships, including the first propeller-driven transatlantic steamship; and numerous important bridges...

 for the South Wales Railway

• The South Wales Railway from Swansea to Carmanthen - 1852 Extended towards Milford Haven in 1854
• New South Wales Railways - 1855 - Sydney
  Sydney
  Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...
  
   to Parramatta

• Powerhouse Museum
  Powerhouse Museum
  The Powerhouse Museum is the major branch of the Museum of Applied Arts and Sciences in Sydney, the other being the historic Sydney Observatory...
  
  , Sydney
  Sydney
  Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...
  
  
• Didcot Railway Centre
  Didcot Railway Centre
  Didcot Railway Centre, located in the town of Didcot in the English county of Oxfordshire, is based around the site of a comprehensive "engine shed" which became redundant after the nationalisation of the UK railways, due to the gradual changeover from steam to diesel motive power.-Description:The...
  
  , Oxfordshire
  Oxfordshire
  Oxfordshire is a county in the South East region of England, bordering on Warwickshire and Northamptonshire , Buckinghamshire , Berkshire , Wiltshire and Gloucestershire ....
  
  

Secondary usage

The large extent of Barlow rail laid in the routes influenced by Brunel, and in New South Wales, has left a legacy of fence posts, and in some cases bridge decks:

• South Devon Railway
  South Devon Railway
  South Devon Railway could mean:* South Devon Railway Company - the company that built the railway from Exeter to Plymouth* South Devon Railway Trust - the heritage railway from Totnes to BuckfastleighOther heritage railways in South Devon include:...
  
   - underbridge
• Conwy Valley Line
  Conwy Valley Line
  The Conwy Valley Line is a railway line in north Wales. It runs from Llandudno via Llandudno Junction to Blaenau Ffestiniog, and was originally part of the London and North Western Railway, being opened in stages to 1879...
  
   - underbridge
• Shipton on Cherwell Halt - fencepost
• Dorrigo Steam Railway and Museum
  Dorrigo Steam Railway and Museum
  The Dorrigo Steam Railway and Museum in Dorrigo, New South Wales, Australia is a large, privately owned collection of preserved railway vehicles and equipment from the railways of New South Wales, covering both Government and private railways...
  
  
• Fairford
  Fairford
  Fairford is a small town in Gloucestershire, England. The town lies in the Cotswolds on the River Coln, about east of Cirencester, west of Lechlade and north of Swindon. Nearby are RAF Fairford and the Cotswold Water Park.-Schools:...
  
  branch - structures