building techniques and materials: Europe 151 had solved the problem by building thick, heavy piers of stone and concrete A pier was a vertical structure intended to bear outward-pushing weight in buildings Such piers meant that interior spaces of churches and manor houses could be constricted, because of the space the piers required In churches it meant that members of a congregation would have their views of the altar and the religious rites blocked By the beginning of the Romanesque era in about 1050 the master stonemason had become a fixture of building construction Master stonemasons directed all aspects of construction of a building and tended to be multitalented Although they were often illiterate, they knew geometry and mathematics, could use a variety of tools, and often were skilled in more than one aspect of construction Those who hired them sometimes noted with satisfaction that they had master stonemasons who could skillfully carve both stone and wood Typically, master stonemasons traveled to where they could find work, and even the least accomplished of them frequently would work in eastern Europe, Scandinavia, France, and England during their lifetimes Builders of castles and cathedrals competed with one another for the services of the best stonemasons, which meant that master stonemasons were treated respectfully, even by bishops and nobles The master stonemasons deserved the respect they were given, because they often had to oversee the work of several thousand laborers while managing expenses and the importation of materials Stone was often imported from quarries in eastern Europe, while the logs that would become the huge beams of cathedrals were imported from Norway and Sweden, sometimes traveling from one edge of Europe to the opposite edge Working under the command of master stonemasons, like officers in an army, were masters of the crafts necessary for constructing buildings of wood and stone Although stones meant to be decorative—that is, visible—were often imported, for most constructions a nearby quarry, still often dozens of miles away, had to be identified A quarry master supervised the removal of stones from it, and a master stonecutter was placed in charge of dressing the stones There was a master mortar maker who oversaw the making of the mortar that was used to hold stones or bricks together It was vital that he see to it that mortar dried properly There was also a master roofer, who had to be skilled in the use of wood, stone, concrete, and lead, which often was used in quarterinch layers on roofs to prevent rainwater from seeping into the structure The master carpenter supervised not only the carving of wood for buildings but also the mechanical devices used to put wooden beams and boards in place The master blacksmith directed the making of nails, latches, and metal bars that were sometimes used to hold stone blocks in place The master glass maker became important during the Gothic era (roughly 1150–1550 in most of Europe, with Italy moving into the Renaissance in the 1400s) because advances in architectural design allowed walls to be thin enough to contain numerous windows Artists were hired to paint glass for windows, to carve wooden altar pieces, or to sculpt stone, though carpenters and stonemasons often did these tasks themselves, depending on the budget of the building project By the 1200s the toolkit of construction workers had expanded to dozens of tools There were hammers, axes, chisels, and levers for cutting and moving stone There were hammers and wedges for splitting wood, big saws for crosscutting tree trunks and large branches, several different planes for smoothing wood, augers for drilling wood, and braces and bits for drilling fine holes in wood A brace and bit consisted of a handle bent in the middle like a staple, with a loose grip that allowed the carpenter to spin the handle in a circle; the business end could have one of several different sizes of bit for drilling into the wood In the 1300s treadle-driven lathes for shaping wood became common Although most European houses remained wooden structures that relied on heavy posts to hold both roofs and walls, as the medieval era progressed, demand for large public buildings increased The increasing size and complexity of buildings meant that humans carrying loads on their backs alone could not handle transporting all the construction material required By the Gothic era the windlass had come into common use for help in constructing buildings large and small It consisted of a drum wound with rope and a crank on the side of the drum to turn the drum, thus winding the rope and raising whatever was attached to the other end of the rope The windlass was often coupled with pulleys for raising heavy loads A pulley was a wheel with a grooved rim in which a rope was set It would be set in scaffolding or other wooden framework above the windlass and above the load to be hoisted and would turn as the windlass was cranked The force a windlass could apply was limited to the strength of people turning cranks on its two ends, but medieval builders needed great force for raising the heavy Scandinavian logs used in tall roofs as well as large stones and prefabricated concrete parts for walls and roofs They adapted an ancient Roman device for this purpose It consisted of a large wheel that looked much like the wheel in cages for rats or hamsters today One or more men would trudge in it, turning the wheel, which would turn a large windlass In towering cathedrals and other tall buildings this large wheel would be placed high on scaffolding, at about the level where beams, stones, or concrete needed to be delivered, and it was almost always attached by rope to a large pulley