How Specs Live Forever

The US Standard railroad gauge (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 the US railroads were built by English expatriates.

Why did the English people build them like that? Because the
first rail lines were built by the same people who built the
pre-railroad tramways, and that's the gauge they used.

Why did "they" use that gauge 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 the wagons use that odd wheel spacing? Well, if
they tried to use any other spacing the wagons 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 roads have been used ever since. And the
ruts? The initial ruts, which everyone else had to match for fear
of destroying their wagons, were first made by 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 questions. The United
State standard railroad gauge of 4 feet, 8.5 inches derives from the
original specification for an Imperial Roman army war chariot. 

Specs 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 war horses.