Thus, partly from circumstances, and partly by their own design, the colonies in 1750 were developing a political life of their own. Changes of dynasties and of sovereigns or of ministers in England little affected them. In like manner their social customs were slowly changing. The abundance of land favored the growth of a yeoman class accustomed to take part in the government. Savage neighbors made necessary a rough military discipline, and the community was armed. The distance from England and an independent spirit threw great responsibility on the assemblies. The general evenness of social conditions, except that some men held more land than others, helped on a democratic spirit. The conditions of the colonies were those of free and independent communities. On the other hand, colonial life was at best retired and narrow; roads were poor, inns indifferent, and travelling was unusual. The people had the boisterous tastes and dangerous amusements of frontiersmen. Outside of New England there were almost no schools, and in New England schools were very poor. In 1750 Harvard, Yale, William and Mary, and the College of New Jersey (now Princeton) were the only colleges, and the education which they gave was narrower than that now furnished by a good high school. Newspapers were few and dull. Except in theology, there was no special instruction for professional men. In most colonies lawyers were lightly esteemed, and physicians little known. City life did not exist; Philadelphia, Boston, New York, and Charleston were but provincial towns. The colonies had only three industries,--agriculture, the fisheries, and shipping. Tobacco had for more than a century been the staple export. Next in importance was the New England fishery, employing six hundred vessels, and the commerce with the West Indies, which arose out of that industry. Other staple exports were whale products, bread-stuffs, naval stores, masts, and pig-iron. The total value of exports in 1750 is estimated at £814,000. To carry these products a fleet of at least two hundred vessels was employed; they were built in the colonies north of Virginia, and most of them in New England. The vessels themselves were often sold abroad. With the proceeds of the exports the colonists bought the manufactured articles which they prized. Under the Navigation Acts these ought all to have come from England; but French silks, Holland gin, and Martinique sugar somehow found their way into the colonies. The colonists and the home government tried to establish new industries by granting bounties. Thus the indigo culture in South Carolina was begun, and many unsuccessful attempts were made to start silk manufactures and wine raising. The method of stimulating manufactures by laying protective duties was not unknown; but England could not permit the colonies to discriminate against home merchants, and had no desire to see them establish by protective duties competitors for English manufactures.