Re: History - OT & not OT

Hi Doug,

My understanding is that the UK practice of driving on the left started in 1733 with a "keep left" rule for traffic on London Bridge and gradually spread from there. As to why we in the US are almost alone among former British possessions (with the exception of course of Canada) in driving on the right, all that I can think of is that there were so few wheeled vehicles on the roads here in the American colonies prior to 1776 that such a rule was never required even in the biggest cities like Boston, New York, or Philadelphia, and by the time road traffic had increased to the point that it was necessary to institute traffic laws in the US in the 19th century we had already substantially diverged from the practices of the "Mother Country".

The original reason for drivers of carriages or automobiles to be positioned on the inside (right side of the vehicle in a "keep left" country such as the UK, or left side in a "keep right" country such as the US), is so that they can stop and speak to each other face to face when approaching from opposite directions. It's all about supporting civil society and the free flow of information.

Similarly, I've been told the reason for positioning the engineer/driver of a locomotive on the outside (left side in a left-hand running country like the UK, right side in a right-hand running country like the US) is to ensure his ability to read trackside signals, whether human or mechanical. So it's also about the flow of information, just from a different source.

-Philip Marshall