The U.S. standard railroad gauge
-- the distance
between the rails -- is 4 feet 8.5 inches.
That's an exceedingly odd
number. Why was
that gauge used?
Because that's the way they built
them in England,
and U.S. railroads were built by English expatriates.
Why did the English build them
Because the first rail lines were
built by the
same people who built the pre-railroad tramways, and that's the gauge
But why did they use that
Because the people who built the
the same jigs and tools that they used for building wagons, which used
that wheel spacing.
Okay, why did the wagons have that
odd wheel spacing?
Well, if they tried to use any
other spacing the
wagon wheels would break on some of the old long distance roads
England, because that's the spacing of the wheel ruts.
So who built those old rutted
The first long distance roads in
built by Imperial Rome for their legions. The roads have been
And the ruts?
The initial ruts, which everyone
else had to match
for fear of destroying their wagon wheels, were first made by Roman war
chariots. Since the chariots were made for Imperial Rome they
all alike in the matter of wheel spacing.
Thus we have the answer to the
The U.S. standard railroad gauge of 4 feet 8.5 inches derives from the
original specification for an Imperial Roman war chariot.
Specifications and bureaucracies
So the next time you are handed a specification and wonder what horse's
ass came up with it, you may be exactly right. The Imperial Roman
war chariots were made just wide enough to accommodate the rear ends of
two war horses.
Now here's a modern twist to the
When we see a Space Shuttle sitting on its launch pad, there are two
booster rockets attached to the sides of the main fuel tank.
are solid rocket boosters, or SRBs. The SRBs are made by Thiokol
at their factory at Utah.
The engineers who designed the
have preferred to make them a bit fatter, but the SRBs had to be
by train from the factory to the launch site. The railroad line
the factory had to run through a tunnel in the mountains. The
had to fit through that tunnel. The tunnel is slightly wider than
the railroad track, and the railroad track is about as wide as
So, the major design feature of
what is arguably
the world's most advanced transportation system was based on the width
of a horse's ass.