A series of letters in New Scientist for October 23 revives the discussion over why different countries insist on motorists driving on the left or on the right, without any apparent logic. Left hand driving is of respectable antiquity, since archaeology demonstrates quite clearly that the Romans drove their chariots on the left of their roads, the remains of tracks bearing witness. British and Australian drivers maintain this system, whereas on the Continent the law has prescribed otherwise. The logical basis for this difference is not evident.
The rulers of old, whether Norman invaders or others, rode their steeds down the left side of tracks, so that the usually right-handed warrior had a better chance of drawing his sword in emergency. In response to this custom the peasant on foot would keep to the right of the track, where he could better spy any approaching danger.
It is claimed that Robespierre, outlawed and guillotined in 1794, induced republican France to take to the right side of the road with its coaches so that the left-sider should not be suspected of nobility and sent to the guillotine on the off-chance. Napoleon, originally a stalwart republican and even then suspected of being hand in hand with Robespierre to make trouble, turned dictator once in power, and so prescribed the hereditary right of the highway. Also, he was supposed to be left-handed and preferred to dismount on the traditional side of his horse on the side of the hedge rather than that of the traffic. Another dictator, Adolf Hitler, prescribed the right throughout Europe.
In the days of the stage coaches, the drivers, sitting on the right of the driving seat, preferred to pass the other traffic on their right, the better to manage their long whips and judge their clearance. Logic, therefore suggests driving on the left of the highway, and why this should not appeal to our continental neighbours is hard to understand.