building techniques and materials: Asia and the Pacific ginning around 2700 b.c.e Mesopotamians began manufacturing plano-convex bricks A mold would give a brick a flat bottom and flat sides (planes) The top, however, bulged or curved out, forming a convex surface It was this convex surface that faced out and became the exterior wall of a structure The plano-convex brick was confined to Mesopotamia, and even there this shape was mostly abandoned after 2400 b.c.e Mesopotamian brick makers after that time scraped off any excess mud, making every surface a flat plane This technique would be used by all other Near Eastern brick makers, including the Persians Once shaped, a brick was removed from the mold to dry and harden The hardest mud bricks were those baked in ovens However, it was easier to let bricks dry in the sun, the trade-off being that sun-dried bricks were not as strong as oven-baked ones Once dried, by whatever method, the brick was ready for use, primarily in building walls Brick walls were built up one horizontal layer, or course, at a time Each course had to be cemented to the course under and over it, using any one of a number of methods Workers could simply press wet bricks together and let them harden in place More commonly they used mortar, a moist substance that adhered the courses to one another when it dried The most usual mortar in the Near East was clay or mud mixed with straw or grit In Mesopotamia another common mortar was bitumen, a black, sticky petroleum material that seeped up from the area’s underground oil deposits Bitumen and other mortars were also used as plaster coverings for brick constructions Mud bricks, even baked ones, needed protection from sun, wind, and rain Plastering them once a year protected them from disintegrating over time Walls made of stone were also built in courses and were often cemented together with mortar One form much favored by the Phoenicians did not use mortar but rather stones shaped into equivalently sized rectangles that fitted tightly together Then the blocks were laid in courses in which groups of three of four stones had their ends facing out of the wall while other groups had their long sides exposed Th is alternation of the ends and sides of wall stones increased the wall’s stability and helped prevent its collapse Another method of stabilizing both stone and brick walls was to add buttresses that kept heavy walls from collapsing under their own weight Although buttresses take a variety of shapes, in the ancient Near East they were flat pillars of brick or stone that projected out from a wall The buttress transferred the outward force that the wall’s weight exerted down into the ground Walls could also crumble under the weight of a building’s roof However, by resting the rafters that supported the roof on buttresses, builders could partially relieve the wall of carrying the load Walls could also be weakened by being pierced with openings for doors and windows The absence in Mesopotamia and other parts of the Near East of wood or stone to reinforce window frames and doorjambs also meant the absence of full support for the wall above Consequently, 155 windows were often kept small and narrow, a single brick’s width, for instance By carving windows out of single blocks of stone, the Persians were able to increase the size of these window openings for their public buildings The stone frame provided the necessary strength to hold up the brick wall above it Doors also were made as small as possible Some early Near Eastern houses even had doors so low and set so narrowly that people crawled through them to reach the interior Larger doors became possible through reinforcement Builders placed two upright posts, or jambs, on either side of the opening and then laid a beam of wood or a stone, known as the lintel, across the top of the jambs The lintel transferred the weight of the wall above the door down to the jambs An exceptionally large doorway or the gateway in a city wall would have buttresses against either side as added bracing Lintels were not sufficiently strong to bear the weight of large expanses of wall They would break under such weight Thus for entryways in large walls, Near Eastern builders used the arch, which was invented in Mesopotamia by the Sumerians in the fourth millennium b.c.e The most common type of arch in the ancient Near East was the corbeled arch A corbel is a brick or block of stone that sticks out of a wall and on which another building element, a rafter or a beam for example, rests for support In a brick corbeled arch—most made of brick—the object being supported was another brick Th is second brick would itself stick out over the end of the fi rst brick On top of the second brick a third brick was laid, also projecting beyond its support As one overlapping brick was added to another, gradually the side of the arch rose, looking much like a series of brick steps From the other side of the entryway, another brick staircase rose to meet its counterpart, forming the apex of a triangle ASIA AND THE PACIFIC BY KIRK H BEETZ Little is known about what ancient peoples of Oceania built Many lived in caves even into the modern age, and others probably lived in huts made of branches and sticks On Easter Island, where people arrived around 400 c.e., there is evidence of such huts, but most of the people lived in caves they dug in the slopes of the island For much of eastern Asia, little has been uncovered for Neolithic structures, probably because they were either temporary or built from perishable materials, principally wood In the prehistoric era the peoples of the Indian subcontinent and Southeast Asia built domed homes of mud, and their tombs for local leaders were typically large mud domes called stupas When the Buddha died in 483 b.c.e., his cremated remains were divided among eight stupas, but in 260 b.c.e., King Asoka opened seven of these stupas and divided the remains among 84,000 stupas throughout most of India One of these is the Great Stupa in Sanchi in central India,