Four Feet, Eight and a
Standard gauge railway lines are used throughout New South
Wales & on Australian National Railways' interstate lines.
It is also the primary gauge used in Britain, Europe, the USA,
& many other countries. It is used on such high speed lines
as France's TGV, Germany's ICE, & Japan's Bullet
Standard gauge, in railway terminology, means a
distance between the rails of 4 feet, 8 ½ inches or 1.435
metres. That's an exceedingly odd number. Why was that gauge used?
Because that's the way they built them in England, & English
expatriates built railways all around the world. Why did the English build them like that?
Because the first railway lines were built by the same people who built
the pre-railway tramways, and that's the gauge they used. Why did they use
that gauge in England, then?
Because the people who built the tramways used the same jigs and tools that
they used for building wagons, which used that wheel spacing. Okay! Why did
their wagons use that odd wheel spacing?
Because, if they tried to use any other spacing the wagon wheels would break
on some of the old, long distance roads. Because that's the spacing of the old
wheel ruts. So who built these old rutted roads?
The first long distance roads in Europe were built by Imperial Rome for the
benefit of their legions. The Roman roads have been used ever since. And the
The original ruts, which everyone else had to match for fear of destroying
their wagons, were first made by the wheels of Roman war chariots. Since the
chariots were made for or by Imperial Rome they were all alike in the matter
of wheel spacing.
Thus, we have the answer to the original question. The standard railway gauge of 4 feet, 8 1/2 inches derives from the original specification
for an Imperial Roman army war chariot.
Specifications and Bureaucracies Live Forever.
So, the next time you are handed a specification and wonder what horse's ass
came up with it, you may be exactly right. Because the Imperial Roman chariots
were made to be just wide enough to accommodate the back-ends of two
And the Space Shuttle?
Plus, there's an interesting extension of the story about railway gauge and
horses' behinds. When we see a Space Shuttle sitting on the launch pad, there
are two big booster rockets attached to the sides of the main fuel tank. These
are the solid rocket boosters, or SRBs. The SRBs are made by Thiokol at a
factory in Utah. The engineers who designed the SRBs might have preferred to
make them a bit fatter, but the SRBs had to be shipped by train from the
factory to the launch site. The railway from the factory runs through a
tunnel in the mountains. The SRBs had to fit through that tunnel. The tunnel
is slightly wider than a railway track, and the railway track is about as
wide as two horses' behinds.
So a major design feature of what is arguably the world's most advanced
transportation system was originally determined by the width of a horse's ass.
Origin unknown. Obtained from http://www.pastornet.net.au/jmm/ahmr/index.htm.
Revised for the Blue Mountains Railway Pages.
Australian Railway Gauges
Australia's state-run railways have not been known for cooperating in the
past. Whilst NSW adopted standard gauge, Victoria chose broad gauge
(5'3"), Queensland, Tasmania & Western Australia went for 3'6"
narrow gauge, & South Australia decided on both broad & narrow. Today,
standard gauge connects Brisbane, Sydney, Melbourne, Perth & Alice
Springs. Victorian Railways also built four 2'6" narrow gauge lines, one
of which has been preserved as Puffing Billy. Queensland is now running
high-speed tilt-trains on its narrow gauge network.