Wednesday, May 25, 2011


Last week, my neighbor and co-author of, asked if anyone knew why the distance between the rails was whatever it was. He also said possums were not allowed to answer. Sigh. Maybe because this possum told him this bit of “information” some time ago, and he remembered it. Now whether it is right or wrong, or just a bit of truth or absolute fact doesn’t matter in the telling of a good story. What matters is if people REMEMBER it. Right?

The story I passed along to my neighbor was this one:

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 English expatriates built the US Railroads.

Why did the English 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 have that particular 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 in England, because that's the spacing of the wheel ruts.

So who built those old rutted roads?

Imperial Rome built the first long distance roads in Europe (and England) for their legions. The
roads have been used ever since.

And the ruts in the roads?

Roman war chariots formed the initial ruts, which everyone else had to match for fear of
destroying their wagon wheels. Since the chariots were made for Imperial Rome, they were all alike in the matter of wheel spacing.

The United States standard railroad gauge of 4 feet, 8.5 inches is derived from the original
specifications for an Imperial Roman war chariot. 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 war chariots were made just wide enough to accommodate the back ends of two war horses. Now the twist to the story...

When you see a Space Shuttle sitting on its launch pad, there are two big booster rockets
attached to the sides of the main fuel tank. These are solid rocket boosters, or SRBs. The SRBs are made by Thiokol at their factory at Utah. The engineers who designed the SRBs would 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 railroad line from the factory happens to run through a tunnel in the mountains. The SRBs had to fit through that tunnel. The tunnel is slightly wider than the railroad track, and the railroad track, as you now know, is about as wide as two horses' behinds.

So, a major Space Shuttle design feature of what is arguably the world's most advanced transportation system was determined over two thousand years ago by the width of a horse's ass. ... and you thought being a HORSE'S ASS wasn't important!

Now there are more facts than this story mentions, and they can get very tedious, so I won’t bore you with them. But I will say this. The first time I heard any explanation about the ruts in old Roman roads was from an archeologist friend, somewhere in Italy, (or was it in Ephesus?) but she gave the credit to a team of oxen pulling carts for the wagon wheel distance – then the Roman chariot wheel spacing followed. Somehow the horse’s ass has a funnier ring than the ass of an ox. Actually, that sounds confusing, but I won’t go there, either.

Then another friend challenged me with the ‘narrow gauge’ tracks used in this country. That answer is simple, too. The smaller carts were used in mining and were pulled by a single animal, usually a mule. If you wade thru some of the histories of the early coal mines in PA, particularly the biography of Josiah White, you can learn a lot of amazing things – like the very first tracks carrying anthracite to the Lehigh River where it was then carried by barge to the southern cities- were made of wood! It took me a whole summer to wade thru that book, but it really had some fascinating information about the very early destruction of the land, as the Europeans “tamed” the wilderness in Pennsylvania, deforested miles and miles of forest, and began mining anthracite along the Lehigh and Susquehanna rivers. Interesting, but not as entertaining. The wooden rails had to be replaced constantly as the weight of the coal quickly shattered even the hardest wood.


Ginnie said...

Wow...I'm impressed. It sounds like you really did the research on this. I can't believe that the narrowness of a tunnel could determine the width of a part of the Space Shuttle !!
There's got to be a better way.

ancient one said...

That story is amazing... and funny!!

Beatrice P. Boyd said...

Sure learned a lot from this post, Possum. Now I will sure be ready if anyone posts similar questions on blogs!

troutbirder said...

Oh my. How these stories take on a life of their own. I really enjoyed you Leopold quote.