Long distance travel and military. I'm not fully sure though.
The Market Revolution (1793–1909) in the United States was a drastic change in the manual-labor system originating in the South (and soon moving to the North) and later spreading to the entire world. Traditional commerce was made obsolete by improvements in transportation, communication, and industry.
Some reasons were because of political, religious,economical,exploratory,medical,scientific,aggressive or ethnocentric reasonings.
In 1766 parliment repealed the stamp tax because English merchants suffered from colonial boycott of English goods. Ships are in the harbor representing the Rockingham Ministy, with Lord Conway and Lord Grafton.