What's All This Vice Versa Stuff, Anyhow? (Part II)

Aug. 9, 1999
I was crossing the Atlantic for the fourth time this year recently, en route to wandering around Europe, and I realized I had a good story. I had explained this story to several people. So I...

I was crossing the Atlantic for the fourth time this year recently, en route to wandering around Europe, and I realized I had a good story. I had explained this story to several people. So I decided to write it down and pass it along to all you guys.

WHY? Why do the French and the Americans and many other people drive on the WRONG side of the road? Why do the British and Indians and Thais drive on the OTHER side? Almost nobody knows how this happened. Here's why:

Back in Roman times, the Roman armies often marched on the road. They did not have vehicles to carry them, so they had to march. The enlisted men had to march on the left-hand side of the road, near or even in the ditch. The General walked, of course, on the high middle part, the crown of the road, where it was not so muddy.

Why did he force the rest of the army to be on HIS left? Because he held his sword in his right hand, and he could defend himself best from any attackers if he had other people on his left side. (The guys on the left did not have such good luck, as they might have to defend themselves from attackers on their left. But when you are an enlisted man, your main priority is to defend the general...) So, barring the remote possibility of a left-handed general, the Roman armies marched on the left side of the road.

(A related theory says that when the Roman general rode in a chariot, near the left-hand edge of the road, he held his reins in his left hand and his sword in his right. And he drove his chariot on the left side of the road. That theory is consistent with the preceding paragraph.)

The Roman army went all over Europe and even to much of England. The Romans built rather good roads. And when merchants or private citizens met the Roman armies, they too were obliged to walk on the left side of the road. And that was how things stayed for over 1700 years.

When Napoleon Bonaparte came to power, about 1805, he was a strong iconoclast. If any other army came along on its left side of the road, he would oppose it by marching on the right side of the road. He was a contrarian. Napoleon conquered almost all of Europe, and his rules caused everybody in Europe to walk and drive their carts on the RIGHT-hand side of the road. But he never conquered England. So the English continued to drive on the left.

The Americans, just like Napoleon, were very contrarian. Whatever the British did, the Yankees would do the reverse or perverse way. When did this occur? Perhaps even before Napoleon did it! I'd always thought that Napoleon did it first. But in retrospect—when I started to write this down—I realized that when you start writing things down and crystallizing your thinking, ideas come into conflict. I bet it will be hard to find (even in my excellent set of Encyclopedia Britannicas from 1894) the time when these changeovers occurred.

But anyhow, this is why England and many other countries that got their automotive commerce and culture from England—such as India, Australia, Thailand, and Japan—drive on the left-hand side of the road.

And most of the rest of the world drives on the right out of this sheer contrariness, after about 200 years. While travelling in France, I heard a variation on this theory: The French changed to drive on the right side of the road at the time of the French Revolution, about 1789, before Napoleon's time. This is entirely possible—the French revolutionaries were contrarians, too. But that theory STILL places this change in France, after the American Revolution.

Has anybody changed, switched over? Yes, Sweden made its change about 35 (that's a guess) years ago. They made sure everybody got home on a Friday night, and then the highway workers got busy, unveiling all new signs for driving on the right, to be in conformance with the rest of mainland Europe. No driving (other than emergency vehicles) was permitted until Monday, and then the speed limit was set at 25 mph until everybody had mastered the new procedures.

(Hey, while lecturing in Europe, I had two good foils. The first one made everybody smile, grin, and titter: "In Theory, there's no difference between Theory and Practice..." That slide was always well-received. But the following one got the ovation: "...but in Practice, there usually is a difference.")

I'm sure glad I never had to drive in a left-hand-drive car, with the driver on the left, in a place where I had to drive on the left-hand side of the road! I depend on the steering-wheel's position to tell me what side of the road to drive on. If I had to drive a British car to France, I would be terribly nervous that I'd make mistakes. Or a French or other left-hand-drive car in England. I'd probably refuse to do it. I just got back from driving a few miles in England and 1900 kilometers in France—always with the steering wheel nearer to the center-line of the road. I can live with that.

I heard some people pooh-pooh these "reasons." They said that the left/right choice is purely arbitrary. I don't think so. In most cultures throughout the world, a horseback rider mounts his horse from the horse's left side. (I recall that some Native Americans did it from the horse's right?)

If you are standing on the crown of the road, and the horse is standing slightly lower than you are, that puts you facing along the right-hand side of the road as soon as you are in the saddle. So any culture where horseback riding is dominant may favor riding on the right, as we Americans do. Or—can you tell me any society where the rider mounts the horse from the horse's right? Can you give any examples of why a rider would like to stand at the lower level, in the ditch, and mount a horse standing at the higher level, on the crown of the road? That might be a place with TALL men and short horses....

But here is a fly in the ointment: In the northern hemisphere, whirlwinds and tornadoes tend to whirl counter-clockwise. When oncoming cars pass, they usually set up little vortices. When these cars are driven on the right-hand side of the road, they generate counter-clockwise vortices. These might be blamed for seeding a whirlwind or tornado. So maybe Oklahomans and Kansans are causing a lot of their own problems with their traffic patterns. Maybe they ought to swap their cars—and their road signs—with the Aussies? That would alleviate problems in both hemispheres....

All for now. / Comments invited!
RAP / Robert A. Pease / Engineer
[email protected]—or:

Mail Stop D2597A
National Semiconductor
P.O. Box 58090
Santa Clara, CA 95052-8090

P.S. It sure is fun to tool around England in a left-hand-drive car, with a big DOG in the right-hand passenger seat. Likewise for a British car in the USA with a dog on the left seat. Shakes up the natives. Jolly fun!

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