Happened upon this article and I wanted to share it.
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? Well, because that’s the way they built them in England, and English engineers designed the first US railroads. Why did the English build them like that? Because the first rail lines were built by the same people who built the wagon tramways, and that’s the gauge they used. So, why did ‘they’ use that gauge then? Because the people who built the tramways used the same jigs and tools that they had used for building wagons, which used that same wheel spacing. Why did the wagons have that particular odd wheel spacing? Well, if they tried to use any other spacing, the wagon wheels would break more often on some of the old, long distance roads in England . You see, 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 (including England ) for their legions. Those roads have been used ever since. And what about the ruts in the roads? Roman war chariots formed the initial ruts, which everyone else had to match or run the risk of destroying their wagon wheels. Since the chariots were made for Imperial Rome , they were all alike in the matter of wheel spacing. Therefore the United States standard railroad gauge of 4 feet, 8.5 inches is derived from the original specifications for an Imperial Roman war chariot. Bureaucracies live forever. So the next time you are handed a specification/procedure/process and wonder ‘Who came up with this?’, you may be exactly right. Imperial Roman army chariots were made just wide enough to accommodate the rear 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 in 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, and 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. 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.
Sigh. See Are U.S. Railroad Gauges Based on Roman Chariots? | Snopes.com – the similarity is coincidental, more related to the fact that carts on both roads and early horse-drawn trackways were sized to allow them to be drawn by two horses side by side, and the first railroads copied the trackway gauge. As late as the Civil War, the South had three different track gauges different from the North’s standard 4’ 8.5" gauge, and narrow-gauge railways were used where the standard gauge was impractical.
I don’t recall the Romans using chariots for war (certainly not during the Empire), and I doubt two of any sort of emaciated equine would fit between standard gauge rails. Most chariots used a central pole with a pair or quartet of horses evenly distributed on either side. But if you space a pair of shafts to accommodate a pony between them to haul a cart other practical dimensions will tend to give a wheel spacing around four and two-thirds feet. Stephenson’s original railways were 4ft 8 inches (1422mm) before adding the extra half inch (1435mm) - while retaining the original wheel spacing to allow for some play to reduce binding on tighter radius curves.
What is true is that Stephenson started his career in Northumberland and Durham, and the threshold of the east gate of Housesteads does exhibit “Standard Gauge” ruts…
The only British chariot burial (Newbridge) where the wheel gauge can be determined is 1.35m.
The tendency to adopt “narrower than standard” gauges were usually dictated by limited financing during the construction phase or by extremely challenging rough terrain.
It is however true that the current world “standard gauge” can be traced to the spacing of Roman chariot wheels.
The current diameter of the SRB’s used for the SLS are also dictated by these same railroad restrictions. In fact they are the same modular rocket units as those used of the Space Shuttle with just on additional module added vertically to give the SLS a longer burn time.
The history of track gauges are varied and all are interesting. At one point, there were as many miles of narrow gauge track in the US as there was standard gauge interurban track, if I recall. I read in one of the older railroad books that at one point around the turn of the century (19th to 20th) that one could get on an interurban in Maine, and go all the way out to Denver on interurbans, with only about a 4-mile gap.
It is certainly amusing…
I know more about Roman forts than I do about railways but I can confirm that at least one has a standard gauge line running through it’s gate. In about 1850 the Whitehaven and Furness Junction Railway made a cutting through the platform of the fort at Ravenglass along the line of the Via Principalis from the north gate (Porta Principalis Dextra) to the south gate (Porta Principalis Sinistra). The western third of the fort (Praetentura) has been mostly lost to coastal erosion but the slip face nicely shows the (shallow) stratigraphy. The rear (eastern) part of the fort (Retentura) was forested but I understand it has been recently cleared, beyond are upstanding remains of what is usually identified as a bathhouse. About a quarter mile north of the fort and adjacent to the main line station is the western terminus of a seven-mile long 15-inch gauge railway.
La’al Ratty:
Assorted Loco’s: Ravenglass & Eskdale Railway - Welcoming Whillan Beck (youtube.com)
Ravenglass to Dalegarth: A Front-Row Journey on the Ravenglass and Eskdale Railway On River Irt | 4K UHD Autumn Adventure (youtube.com)
Dalegarth to Ravenglass: Ravenglass & Eskdale Railway - Dalegarth To Ravenglass On River Irt - Cab Ride UK Railway [4k UHD] - YouTube
