156 building techniques and materials: Asia and the Pacific which still stands Its mud dome was eventually blanketed by bricks without the use of mortar Although it is known that Indians used wood for building many structures, superseding the use of mud in the north early in recorded history, little is known about the ancient wooden structures because they did not survive long enough Heavy rains and humidity made wood rot quickly Still, a little is known about early wooden buildings from surviving temples carved in stone In about 150 b.c.e., in the Western Ghats mountain range along the west coast of India, rock carvers expanded caves that initially had been homes for religious ascetics, creating spectacular temples and monasteries The ceilings of some of these temples are arched, and representations of wooden beams have been carved into them The carvings show many small wooden beams fitted together to form arches, resembling a technique used in ancient China at that time Iron axes with flat edges were used for the initial dressing of the stone, and fine tools of iron and stone were used for carving images The Indians used the post-and-crossbeam technique, in which two or more posts are set in the ground in a row and beams are laid across their tops to bear the weight of a roof or higher floor while leaving openings that could be fi lled by walls or doors When building with bricks or small stone blocks, they used the corbeling technique to create openings in free-standing stone structures, such as towers A corbeled opening is an arch shaped like an upside down V of steps, in which blocks are set with one end projecting outward and the other end held in place by the weight of blocks piled on it Because they have no mortar to hold them together, the blocks are prone to shifting from the effect of earthquakes or erosion of their foundations, sometimes causing the structures to collapse When building tall stone structures such as gateways, Indians first constructed an outer framework of bamboo that crisscrossed to make squares up which workers could climb Corbeling without mortar created problems for ancient builders that they did not fully solve Most of Indochina and Indonesia imitated Indian building techniques In the region of modern Cambodia, the Funan kingdom of the first through sixth centuries c.e imitated Indian construction techniques, but their tall brick buildings would fall down Later Funan and Angkor (802–1432 c.e.) builders in the region of modernday Cambodia used sand to even out the foundations of their buildings, but water would wash away the sand, and towers would tilt and eventually crumble They tried to solve that problem by hollowing out stones at the bases of buildings and inserting timbers buried in the ground to stabilize tall structures, but in the wet climate the timbers would rot, and the walls and towers would fall These ancient builders and those in Java tried using dowels of iron for holding stones in place, but they required maintenance; iron would rust and fall apart and then so would walls In China, around 4000 b.c.e., the Yellow River culture built homes that were circular, with timber walls shored up on the outside by mounds of dirt and conical thatched roofs that peaked in the middle This basic structure spread to much of eastern Asia, and circular houses were still being built on the island of Honshu in the 200s c.e As the Yellow River culture encountered cultures from the south and north, building protective structures became as important as building homes During the Shang Dynasty (ca 1500–ca 1045 b.c.e.) towns were surrounded by walls of tamped dirt On the northern frontiers, during the Zhou Dynasty (ca 1045– 256 b.c.e.), some small feudal provinces built long walls to deter nomadic northern tribes from invading In 214 b.c.e the emperor Shi Huangdi began to have these various walls connected into the Great Wall The inner part of the wall was fi lled with debris, while stones were laid for the outer parts of the wall This technique became common for building fortifications in China Even though the Great Wall is justifiably renowned, the great genius of Chinese architecture came not in the building of the wall but rather in creating techniques of construction that could be applied to monumental structures and to tiny homes and that were versatile enough to be adapted to different building materials according to availability Thus, in northen China golden loess from desert areas was used for bricks, which were combined with wood to build structures; in central China stone would be combined with wood; and in southern China stone would be combined with bamboo as well as wood All builders followed basic practices developed by the time of the emperor Shi Huangdi: Foundations would be excavated and fi lled with unhewn stone, bamboo or timber frameworks would be created for workers to climb, posts would be set in the foundation to bear most of the weight of the structure, and walls would bear little or no weight The posts would often have to bear immense weight, especially from roofs tiled with earthenware On the top of a post, Chinese workers would place struts, usually of wood, that spread out upward like upturned legs; on their ends would be laid crossbeams or more struts spreading out, and the pattern would be continued as high as needed to reach the bottom of the floor above or the roof; the effect was to draw the weight of a building into the posts This method resulted in buildings that had posts throughout their interiors, often set close together; provided the posts were sturdy, builders could place almost anything they wished onto a structure, which resulted in majestic pagodas, imposing palaces, shops, and houses for rich and poor The ancient Chinese used corbeling for their arches Th is resulted in sometimes awkward public works, especially bridges, which tended to have tall, steep arcs that were very hard for people and carts to traverse while burdened Even as the Great Wall was being built, Chinese engineers were borrowing from the technique of post and crossbeam to lay sturdy stone bridges The stone beams were as long as 70 feet and weighed as much as 200 tons; these beams were smoothed with iron axes, dragged to riversides, lashed across several boats abreast, and floated into place during