Why Some Standards Never Go Away

Note: the following is from an anonymous source I read in a quality magazine. This article is reproduced from memory.

The standard United States railway gage is 4 feet 8 inches; no more no less.
 
Q: Why is the United States railway gage 4 feet 8 inches?
A: That's because U.S. railways were designed by British railway engineers, and their standard gage is 4 feet 8 inches.
 
Q: Why did the British have as their standard 4 feet 8 inches?
A: The people who built British railway cars used the jigs they used to build trams and the jigs were set up for a wheel base of 4 feet 8 inches.
 
Q. Why were British tram jigs set for a wheel base of 4 feet 8 inches?
A. The jigs were originally used to build road carts, and their wheel base is 4 feet 8 inches
 
Q: Why did British road carts have a wheelbase of 4 feet 8 inches?
A: The ruts in the long distance roads in Britain are spaced at 4 feet 8 inches.
 
Q: Why are the ruts on the long distance roads in Britain 4 feet 8 inches apart?
A: These roads were built by the Romans and their war chariots had a wheelbase of 4 feet 8 inches.
 
Q: Why did Roman war chariots have a wheel base of 4 feet 8 inches?
A: The yoke connecting the horses to the chariot had to be wide enough to accommodate two horses.

Footnote: The booster rockets for the space shuttle are built in Utah and shipped to Florida by rail. The rockets have to pass through a rail tunnel. The width of the tunnel determines how wide the rockets can be.

So man's most advanced mode of transportation has been designed, in part, by a couple of horses' asses: 2,000-year-old Roman war horses, to be specific.