Standard and Narrow Gauge in Japan


Use of rails that are 1,435 mm apart (4’ 8.5”) is so common around the world that this has come to be called “Standard Gauge” track. But most of the track in Japan doesn’t use this. Why? Well, that’s something of a mystery, although there are a few facts which point to a fairly obvious conclusion: British influence. It’s also the case that Standard Gauge, while common in modern English-speaking countries, only accounts for a little more than half the rail-miles (or rail-km) in use today, and had a lesser share in the past.

Japan’s Shinkansen lines are all built to Standard Gauge, because trains are more stable, and can go faster, on wider track. Some other lines in Japan use 1,372 mm (4’ 6”) or 762 mm (30”) gauge. But the majority, over 83% in terms of distance, of Japan’s railways are built to Cape Gauge, 1,067 mm (3’ 6”). The name comes from its adoption in 1873 by the Cape Colony (later part of the Union of South Africa). But by then it had been around for nearly a century, originally for horse-drawn railways in England and Wales, and later steam railways around the world, including Australia, Canada and other locations. And, as of 1872, Japan, where it is known as Kyōki (狭軌, literally “narrow path” or “narrow track”). But compared to Standard Gauge, it’s never been all that heavily used outside of Japan. For more detail, and some information on additional gauges and who uses them in Japan, see my Prototype Track page.


Origin of Standard Gauge


Although railways have their ultimate origin in mining technology in Germany c. 1500 AD, common carrier railways are a British invention, first with horses and later with steam engines. And the origins of standard gauge for railway use trace back to one railway engineer, albeit an influential one: George Stephenson. He was influenced by track used in coal mines in his region, notably the Killingworth mine (other areas used other gauges) and chose 1,422 mm (4’ 8”) for the coal-hauling common carrier Stockton and Darlington Railway (originally using horse-drawn wagons) in 1825, with the intent that this would eventually become a standard gauge for public lines.

There’s a myth, or urban legend, that standard gauge spacing derives from the spacing of ruts on ancient Roman roads, put there for “war chariots” and adopted when rails were first laid on existing stone roadways. This is sometimes credited to Stephenson, even though he didn’t design the Killingworth railway. There are several other problems with the idea: first, the Romans never used chariots for war (see this PDF and this history of British use), although they did use a variety of cars, carts and “gigs” (see this history). Second: the earliest known railways, dating from the sixteenth century, were used for hand-pushed mine carts and used a relatively narrow gauge (480 mm, or 1’ 6-7/8”), because mine tunnels were small. And finally, Roman roads outside of cities were often paved in gravel, not stone, and ruts were mainly a feature of locations with close clearances (e.g., urban roads), see this description of roads in Roman Britain.

There is, however, a somewhat indirect relationship of standard gauge to historic trends for wagon design. Many cultures have ended up with wheeled vehicles with a wheel spacing between 4’ 6” (1,372 mm) and 5’ (1525 mm), likely because of trade-offs in wagon capacity and stability (wider is better), roadway construction cost (wider is more expensive), and the desire to use paired draft animals (which have varied in size over the centuries, so no single number is likely to be correct). This covers the range of most larger-gauge railways as well, although there have been both larger (broad gauge) and smaller (narrow gauge) spacings used.

The oldest known implied wheel spacing comes from a Babylonian design for roads made from two parallel rows of stone blocks on 5’ (1525 mm) centers, suggesting that that was the average wheel spacing (in the unlikely case flanged wheels were used, the gauge to the inside of the blocks was about 4’, or 1,220 mm). In this case, 5’ equated to 3 cubits in the measurement system of ancient Babylon, so the spacing may have been simply chosen as a nice round number.

Many ancient societies cut ruts in stone-paved roads to guide wagons where safety (e.g., mountain roads) or clearance (e.g., city roads) were issues. The ancient Greeks made extensive use of ruts, all apparently cut to a standard center spacing of 1,630 mm (5’ 4”). The Romans used ruts in urban streets to guide wagon wheels past the stepping stones used at intersections for pedestrian crossings. These were primarily for delivery wagons as vehicle use in cities was generally prohibited during the day and Romans either walked or were carried in lecticia (litters).

The Roman roads used grooves of about 60 mm width (2 3/8”) and an average spacing of 1,440 mm (4’ 9”), which likely is the source of the urban legend. However, “gauge” refers to the distance between inside edges of the rails, not the center of the rail as a wheel rut would be spaced, so those ruts would have a gauge of 1,380 mm (4’ 6”). And further, while those were the sizes measured in Pompeii and Herculaneum, both geographically close and preserved by the same volcanic eruption, measurements of other Roman cities showed other center-spacings, down to 4’ 6” (1,380 mm). So even in Roman design, there is no reason to believe that there was a single standard in use.

Certainly there is evidence that for thousands of years, many different civilizations have found approximately 1,450 mm to be a good spacing for wheels on a variety of vehicles. That’s also about the width of two horses, so a road had to be at least that wide in most places, but not necessarily much wider, and thus that was an upper bound on wheel spacing in some locations. However, it was approximate at best, and you could say the same thing about five feet (1,525 mm, another common rail spacing). Standard gauge thus relates to pre-railway vehicle design, but it’s not as simple as saying that it copied an existing standard for road construction. Many early railway vehicles were built by existing carriage-makers and were simply wagons or carriages with their wheels replaced, so the size of vehicles chosen by a given railway may have dictated their rail spacing.


Standard and Other Gauges


It’s also a fact that while Standard Gauge is fairly common today, particularly in some countries, that hasn’t always been the case. In the early days a variety of gauges competed, and even today lots of other gauges are in use. As Wikipedia will tell you, Standard Gauge is in use by more than half the railway lines in the world. But when railways were just getting started, things were a lot more free-form, because each railway line was seen as an independent system. It took years, and a fair bit of bureaucracy, for the benefit of running cars, even whole trains, between one company’s rails and another’s to be realized, and even then it was mainly the “common carriers” who did that, many specialty railroads to this day aren’t connected to anyone else and a number still use different gauges.

By the middle of the nineteenth century people had begun to settle on country-specific standard gauges. England was mostly using “standard gauge” by 1846. The U.S. moved more slowly, and although many railroads were standardized earlier, and the 1863 construction of the transcontinental railroad was required by law to use standard gauge, many did not standardize until 1886. Prior to then, 11,500 miles (18,500 km) of 5’ gauge railways existed in the U.S., alongside a variety of other gauges.

Substantial construction in the 1870’s and later was still being done in gauges narrower than standard gauge. Often these were railroads in isolated areas, either specific to an industry (e.g., forestry or plantation railroads) or common carriers in remote places. In the U.S., both Eastern and Western railroads were built in narrow gauge after 1870. Britain used narrow gauges in a number of colonial regions.

The countries of the former Soviet Union also standardized, but on 5’ (1,524 mm), later refined to 1,500 mm (4’ 11”). This was the former Russian Empire’s standard gauge dating from 1842, which in turn was influenced by their hiring of an American engineer who was familiar with 5’ gauge railways in the United States. Today, 1,500 mm is the second most common railway gauge.

In a similar manner, Japan was probably influenced by the engineers it hired to help develop its initial railways, who were largely British, when it adopted 1,067 mm (3’ 6”) as its informal standard gauge for railway construction over the next century. They weren’t unaware of Standard Gauge’s increasing dominance, but they chose another path and stuck to it.

In the middle to late nineteenth century railroads were being built in a number of places that didn’t have the potential for high-volume cargo or passenger traffic. In the absence of good roads, and few roads at that time were more than cart tracks, a railroad was essential to the economic prosperity of a region, or to getting at resources from remote forests (lumber) or mines (coal, iron, etc). It costs less to build a railroad with rails closer together: cuts and fills are smaller, bridges use less wood or iron, and curves can be sharper, which avoids other costs of construction. The downside is that such trains can carry less maximum weight. But on a marginal railroad, building inexpensively is important to long-term financial health. Or so it seemed anyway; the fact that outside of Japan few of these railroads survived into the age of automobiles tends to argue against that being true.


Japan


The first full-size steam locomotive in Japan may have been a 762 mm (30”) gauge one imported to Nagasaki in 1865 by a Scottish trader, Thomas Blake Glover, although there is some controversy over that, and it was never used commercially. The first commercial railroad was built from the port city of Yokohama on Tōkyō Bay to Tōkyō from 1870 to 1872 by a British consulting engineer, George Preston White and a number of other British engineers, including William Morel who oversaw the surveying and construction of the line. The British employees would gradually be replaced by Japanese engineers, many of whom had trained in England. However the decision to use Cape Gauge for this line was made in early 1870, prior to even Morel’s hiring.

Dan Free, in his book Early Japanese Railways: 1853 - 1914 (from which the above Japanese history comes) notes a number of factors that suggest that White made the decision, based on his experience with lines of that gauge being built in India, although there is no documentary evidence. Morel is sometime given the credit instead, but this seems less plausible.

Certainly that first line from Yokohama was built on a budget. The Japanese government was new, and utterly lacking in foreign currency, yet had to hire both expensive consultants and purchase equipment overseas. Money was raised by bonds sold in London guaranteed by future revenue (and further guaranteed by the Japanese government). But there wasn’t a lot of money considering that they had to create a technological system from scratch halfway around the world from suppliers. Cost-saving would have been the name of the game, and narrow gauge had a reputation for reducing initial capital.

Although the government didn’t nationalize the railways until 1906, it took a strong central role in standardization, and apparently chose to continue with the gauge it had started with, causing most later railways to be built to that gauge. Some private railways chose other gauges, including standard gauge, and in particular a number of small regional railways used and still use 762 mm (30”) gauge. But most were built to Cape Gauge.

In subsequent years, particularly from 1909 to 1920, the Japanese would try, repeatedly, to switch to standard gauge out of a desire for higher speed, heavier tonnage, or simply for ease of purchasing equipment overseas. Several of these attempts were put off by the government on military grounds, as the existence of an odd gauge made use of railway lines by a potential invader more difficult. By 1927, the nationalized Japanese Government Railways operated 12,864 km (7,993 mi) of track and it would have been very expensive to convert. And by then, the technology was entirely locally-made, and imports were no longer a concern. It wasn’t until the first high speed Shinkansen line was built in the 1960’s that Japan would finally get a large-scale standard gauge line.

And there you have it: the mystery is still a mystery at heart, but the likely reason most Japanese railways are narrow gauge rather than standard gauge was that original choice by a British engineer, influenced by cost concerns.

References:

Early Japanese Railways: 1853 - 1914, by Dan Free, Tuttle Publishing, 2008
This book covers the early history of railroading in Japan (and is well worth owning for anyone interested in Japanese railroads, even if like me your focus is on modern ones).

The Evolution of Railways, 2nd Ed., by Charles E. Lee, Railway Gazette, 1943
This book covers the historical sources for railway gauges, including ancient roadway design.