Horse Rumps, Railroads, and Space Technology: An Unexpected Connection

The width of railroads in the United States is 4 feet 8.5 inches. At first glance, this is just an odd number, but behind it lies an intriguing story that stretches back thousands of years. Why this particular width? The answer lies in the engineering traditions of England, where the first railroads for the American continent were constructed.

The width of railroads in the United States is 4 feet 8.5 inches. At first glance, this is just an odd number, but behind it lies an intriguing story that stretches back thousands of years. Why this particular width? The answer lies in the engineering traditions of England, where the first railroads for the American continent were constructed.

When English engineers began designing these roads, they used the same standards as for trams. These trams, in turn, were designed with the dimensions of cart wheels in mind, which were standardized for the time. So, we return to the question: why did these carts have such a distance between their wheels? It turns out the reason is that the old roads of England, built long ago by the Romans, were constructed with a specific width to prevent wheel breakage.

Imperial Rome, as we know, left a profound mark on history by building the first long roads in Europe. These roads became the foundation for all subsequent transportation routes. The Roman chariots, used to move legions, had standardized dimensions that ensured their compatibility and reliability. Thus, the width of U.S. railroads ultimately traces back to the size of Roman military chariots, which were wide enough to accommodate the rumps of two battle horses.

But that's not all. An interesting twist in this story happens today. When a space shuttle stands on the launch pad, its two large solid rocket boosters (SRBs) are designed with the railroad width in mind. These SRBs, manufactured by Thiokol in Utah, must be narrow enough to fit through tunnels on the way to the launch site. And as we already know, the tunnels were constructed to match the width of the railroads, which means the distance is again connected to horse rumps.

Thus, one of the key features of the modern spacecraft, which is considered the pinnacle of engineering achievement, turns out to be closely linked to the dimensions of horses used in Rome over two thousand years ago. Who would have thought that such a seemingly insignificant detail, like the width of a horse's rear, governs not only railroads but also space technology?

So the next time you see a railroad or a space shuttle, remember that this entire story began with ancient Roman chariots and their rumps. Who knew that such seemingly minor details could have such a profound impact on technological development?