Roads, artificial pathways formed through a country for the accommodation of travelers and the carriage of commodities. Through the Romans set an example as roadbuilders, some of their public highways being yet serviceable, the roads throughout most of Europe were in a wretched condition till toward the end of the 18th century. France was in advance of other countries in road making; in England a decided improvement of the highways only began in the 19th century. Before the time of Macadam it was customary to use broken stones of different sizes to form the roadway, the consequence being that in course of time the smaller stones sank, making the road rough and dangerous. Macadam early in the 19th century introduced the princicle of using stones of uniform size from top to bottom. What is known as the rule of the road is that in passing other horsemen or carriages, whether going in the same or the opposite direction, the rider or driver must pass on the left hand of the other rider or driver.
Entry from Everybody's Cyclopedia,
1912.