McAdam, who was born in 1756, created roadways with a tougher surface by arranging shattered stones in symmetrical, tight patterns and covering them with smaller stones. His idea, named "Macadam" for himself, was a great accomplishment in road construction in the 1800s. He proposed that all public roads be built with his design, but only some modern highways are still being maintained today. In the South, where most roads had no such improvement, drivers often removed any loose rocks from their path with their hands. The early pioneers were not afraid to drive on rough roads, because they knew that any caravans traveling over these paths would have problems of its own! As cities grew and traffic increased, need for roads also rose. By 1835, when John McAdam died at the age of 67, he had already sold many patents of his ideas to European governments. But he continued to work on his farm near Liverpool until just a few months before his death in 1806. His son took over the business and developed it further by selling merchandise made from Macadam's broken stone to keep costs down. In 1825, Thomas McAdam published A Treatise on Roads and Roadmaking which included detailed instructions on how to arrange the stones for maximum durability. Roads have always played an important role in our economy. Before the advent of the automobile, most commerce was done on foot or by horse-drawn cart.