Craft guilds grew up in the towns, such as the tanners at Oxford, which later merged with the shoemakers into a cordwainers' guild. There were weavers' guilds in several towns, including London, which were given royal sanction and protection for annual payments (twelve pounds of silver for London). They paid an annual tribute and were given a monopoly of weaving cloth within a radius of several miles. Guild rules covered attendance of the members at church services, the promotion of pilgrimages, celebration of masses for the dead, common meals, relief of poor brethren and sisters, the hours of labor, the process of manufacture, the wages of workmen, and technical education. King Henry standardized the yard as the length of his own arm. Trades and crafts, each of which had to be licensed, grouped together by specialty in the town. Cloth makers, dyers, tanners, and fullers were near an accessible supply of running water, upon which their trade depended. Streets were often named by the trade located there, such as Butcher Row, Pot Row, Cordwainer Row, Ironmonger Row, Wheeler Row, and Fish Row. Hirers of labor and sellers of wheat, hay, livestock, dairy products, apples and wine, meat, poultry, fish and pies, timber and cloth all had a distinct location. Some young men were apprenticed to craftsmen to assist them and learn their craft. London had bought the right to have an elected mayor. The Norman word "mayor" replaced "portreeve". Henry I granted the Londoners the right to elect a sheriff and a justiciar from among themselves. London had at least twenty wards, each governed by its own alderman. Most of them were named after people. London was ruled by sixteen families linked by business and marriage ties. These businesses supplied luxury goods to the rich and included the goldsmiths [sold cups, dishes, girdles, mirrors, purses knives, and metal wine containers with handle and spout], vintners [wine merchants], mercers [sold textiles, haberdashery, combs, mirrors, knives, toys, spices, ointments, and potions], drapers, and pepperers, which later merged with the spicers to become the "grocers", skinners, tanners, shoemakers, woolmen, weavers, fishmongers, armorers, and swordsmiths. There were bakehouses at which one could leave raw joints of meat to be cooked and picked up later. These businesses had in common four fears: royal interference, foreign competition, displacement by new crafts, and violence by the poor and escaped villeins who found their way to the city. When a non-freeholder stayed in London he had to find for frankpledge, three sureties for good behavior. Failure to do so was a felony and the ward would eject him to avoid the charge of harboring him with its heavy fine. The arrival of ships with cargoes from continental ports and their departure with English exports was the regular waterside life below London Bridge. Many foreign merchants lived in London. Imports included timber, hemp, fish, and furs.